Even when the European-Iranian agreement to halt Iran's uranium-enrichment program looked solid, the United States was blunt in its disapproval. The ink was barely dry on the accord when the Bush administration, it appears, began trying to derail it.

First, rather than endorse the accord, Secretary of State Colin Powell essentially accused the Iranians of lying when they said their nuclear program was for peaceful purposes. He announced that new intelligence showed Iran is developing a nuclear warhead to arm its Shahab-3 ballistic missiles. Then, at a Nov. 20 meeting of heads of state in Santiago, Chile, President Bush stated unequivocally that Iran is trying to build a nuclear weapon.

Why would the administration take such a combative stance? Because hard-liners within the administration thought Tehran would use the settlement to buy time for building nuclear weapons, and that the United States would be better off bombing Iran's suspected weapons sites.

Proponents of using military force against Iran have not yet won the argument within the Bush administration. But the past two weeks of strong pronouncements about the threat Iran poses suggest that the military option may be gaining ground. And Iran's last-minute attempts to maintain some enrichment capabilities -- which by press time Friday were threatening to kill the European agreement -- no doubt strengthened the hard-liners' hand.

Before the United States even considers such a drastic step as airstrikes against suspected nuclear weapons sites -- or even trying to compel the United Nations to endorse new economic sanctions against Iran -- it is essential that our leaders be clear about what they are trying to accomplish in Iran and whether such actions will help or hurt.

If the ultimate goal is to create a democracy -- one that would not fear the United States and therefore have less use for the bomb -- then dual-track diplomacy with Iran's government and with its people is more likely to work than military action.

Probably the most important question the administration's leaders should ask themselves is whether Iran, even a nuclear-armed Iran, poses a direct threat to the United States and its allies.

The answer, we believe, is no.

The mullahs who rule Tehran long ago gave up their ideological quest to "export'' revolution. Like the last generation of octogenarians who ruled the Soviet Union, Iran's leaders today want nuclear weapons as a means to help them preserve their power, not to help them spread their model of theocratic rule to other countries.

Deterrence works

In other words, even if Iran's rulers succeeded in building nuclear bombs, they would be very unlikely to take on the United States and its vast nuclear arsenal or to attack Israel. (The mullahs in Tehran understand that any nuclear attack against Israel would trigger full retaliation from the United States.) In dealing with Iran, deterrence works.

Tehran would also be unlikely to pass a bomb to Islamist terrorists, despite its support of Arab terrorist organizations that continue to attack Israel. One reason, again, is deterrence. Iran's rulers know that the United States would probably be able to trace the weapon back to them and retaliate.

The threat of a nuclear Iran comes, instead, from the reaction it is almost sure to spark in the region and the world, possibly sending Egypt and Saudi Arabia on their own quests for nuclear weapons.

Such an arms race would undermine the longstanding Treaty on the Non-Proliferation of Nuclear Weapons, an agreement signed by nearly 190 countries, that has proved indispensable in preventing the spread of nuclear weapons.

Bush administration hard-liners want to save that arms-control treaty by using arms. In advocating a "surgical'' military strike against Iran's most important nuclear facilities, including the once hidden enrichment plant in Natanz, they cite Israel's airstrike against Iraq's nuclear complex at Osirak in 1981 as a model of success. They argue that an American (or Israeli) strike would not end Iran's nuclear aspirations, but would dramatically slow its program and make the mullahs reconsider the costs of trying to restart it.

Attack would backfire

But a pre-emptive military strike would instead do just what the hard-liners in Tehran hope for: It would unite their people behind them.

Even a precise bombing campaign would kill hundreds if not thousands of innocent Iranians; destroy ancient buildings of historical and religious importance; trigger an Iranian counterstrike, however feeble, against American targets and friends in the region, and spur the mullahs to increase their direct support for American enemies in the Shiite part of Iraq.

Even more important, an attack would only encourage Tehran to redouble its efforts to build a bomb, just as Saddam Hussein sped up his efforts after the 1981 strike. It would also hurt the democratic opposition movement inside Iran, which is already in retreat and cannot afford another setback. After an attack, Iranians, not unlike Americans, are sure to rally around the flag and their government.

If the administration decides, in the end, that American military options are limited and counterproductive, the only serious way to impede the development of Iranian nuclear weapons is through negotiation. Iran's recent accord with France, Britain and Germany is only temporary, and negotiations are expected to continue.

If the United States were to jump in now, it could try to ensure that our European allies accept nothing less than a permanent and verifiable dismantling of Iran's enrichment capabilities, as well as banning any plutonium production.

Allowing the Iranians to enrich even some uranium, which they say will be used merely to feed their nuclear power plant, makes it too easy to cheat. To make the deal work, the United States would need to join with Europe, Russia and China in pledging to guarantee Iran a permanent and continuous supply of enriched uranium. To make the deal even more attractive, the fuel could be offered at reduced prices.

Even under the strictest inspection regime, Iran's leaders will cheat, as they have often done in the past, and they will eventually divert enriched uranium from peaceful to military purposes. But the harder and more transparent the allies can make it, the longer it will take Iran to begin building bombs.

In the long run, the world's only serious hope for stopping Iran from developing nuclear weapons is the development of a democratic government in Tehran. A democratic Iran will become an ally of the Western world no longer in need of a deterrent threat against the United States.

Democracy in Iran therefore obviously serves U.S. national interests. Yet Bush administration officials (as well as their predecessors in the Clinton, Bush and Reagan administrations) have not succeeded in developing a strategy for advancing the cause of Iranian democracy.

New strategy

What is needed is a radical new approach that would nurture change from within the country, in alliance with Iran's democratic movement, rather than impose change from without.

A first step would be to establish an American presence in Tehran, as many in Iran's democratic opposition have proposed. Now decades old, the U.S. policy of isolating Iran has not weakened but instead strengthened its autocratic government.

Of course, we are not suggesting that the United States open an embassy in Tehran and turn a blind eye to human rights abuses; that would only contribute to the further consolidation of the mullahs' hold on power. But we are suggesting a new strategy that would allow American government officials, as well as civic leaders, academics and business people, to engage directly with Iranian society.

This engagement cannot occur on a widespread scale without some level of diplomatic relations and some revision of the American sanctions against Iran. Then, more Western foundations would be able to make grants to pro-democracy Iranian organizations, while business people -- and especially the Iranian-American business community in the United States -- would be able to leverage their capital and know-how to influence economic and political change inside Iran. A U.S. presence in Iran would, not incidentally, also enhance the West's ability to monitor Iran's nuclear program.

Critics of engagement argue that diplomatic relations with Iran will reward this "axis of evil'' member for years of supporting terrorism and pursuing nuclear weapons. In fact, an American presence in Iran is the mullahs' worst nightmare.

Iran's government has long used its ongoing tensions with the United States, as well as the embargo, as an excuse for the economic difficulties that are, in fact, the direct results of the regime's incompetence and corruption. Tehran's leaders have conveniently labeled nearly all of their opponents as "agents of America.''

Most important, part of the regime's self-declared legitimacy lies in its claim to be the only Muslim country fighting what it sees as U.S. imperialism. If the United States could prove it's not an enemy of the Iranian people, the legitimacy of Iran's leaders would diminish.

Reagan's course

In the first years of his presidency, Ronald Reagan labeled the Soviet Union the "evil empire'' and went out of his way to avoid contact with such a regime.

Over time, however, Reagan charted a new course of dual-track diplomacy. He engaged Kremlin leaders (well before Gorbachev) in arms control, while also fostering contacts and information flow between the West and the Soviet people in the hope of opening them up to the possibilities of democracy.

In the long run, it was not arms control with the Soviets, but democratization within the Soviet Union, that made the United States safer.

If George W. Bush desires a foreign-policy legacy as grand as Reagan's, now is the time to think big and change course as dramatically as Reagan did.

The United Nations High-Level Panel on Threats, Challenges and Change completed its comprehensive review of collective security, recommending historic changes to the U.N. in its report, "A more secure world: Our shared responsibility." Among the panel's 101 recommendations for the U.N. and member states are expansion of the U.N. Security Council and creation of a Peacebuilding Commission to advance proactive, preventive global security measures.

The report culminates a year-long project for which SIIS Senior Fellow Stephen J. Stedman served as research director. The 16-member panel, commissioned by U.N. Secretary-General Kofi Annan and chaired by former Thailand Prime Minister Anand Panyarachun, represents the U.N.'s most comprehensive effort to analyze collective security, since the founding of the international body in 1947. The select panel sought international input in an effort to honor the perspectives of all member states, as it analyzed current threats and identified specific security measures.

Nations are the "front line in today's combat," Annan said, introducing the report. He added, "The task of helping states improve their own capacities to deal with contemporary threats is vital and urgent. The United Nations must be able to do this better. The panel tells us how."

The report identifies six major threats to global security: war between states; violence within states, including civil wars, large-scale human rights abuses and genocide; poverty, infectious disease and environmental degradation; nuclear, chemical, biological and radiological weapons; terrorism; and transnational organized crime.

The panel proposed expanding the U.N. Security Council--for which it put forth two options--as well as creating a Peacebuilding Commission to help the Security Council pursue the recommended preventive security strategies. One proposal for Security Council expansion would appoint new permanent members, and the other would establish new long-term, renewable seats. Neither option creates any new vetoes.

In a cover letter to the secretary-general, Panyarachun thanked CISAC and Stedman for supporting the panel's work. CISAC Co-Director Christopher F. Chyba served on the panel's 30-member resource group, providing expertise on nuclear nonproliferation and bioterrorism. CISAC hosted a nuclear nonproliferation workshop at Stanford for the panel last March, and Panyarachun discussed security issues with representatives from China, India, Pakistan, Russia and the United States at CISAC's Five-Nation Project meeting in Bangkok last summer. Stedman's research staff included Bruce Jones, a former CISAC Hamburg Fellow, and Tarun Chhabra, a graduate of CISAC's undergraduate honors program.

Annan has asked Stedman to stay at the United Nations another year to help gain worldwide support in implementing the panel's recommendations.

The panel's report received prominent news coverage, including a front-page New York Times article ("Report urges big changes for the U.N.," by Warren Hoge, Dec. 4), and in the Economist an invited article by Annan ("Courage to fulfill our responsibilities," Dec. 4) as well as several other pieces in the Nov. 24 and Dec. 4 issues.

Earlier this month, the so-called EU Three--Britain, France and Germany-- achieved an important victory for global security, convincing Iran to suspend its uranium enrichment and plutonium reprocessing activities pending further negotiation on its nuclear question. Though Iran claims that it does not desire a nuclear bomb, the West has long been skeptical of the oil-rich state's contention that it seeks a nuclear fuel cycle for energy purposes alone. Europe and the United States (and of course Israel) will sleep better knowing that Tehran is not pursuing enrichment activities, whatever their alleged purpose.

But the EU3 agreement, which fails to discuss consequences for Iran if it breaks the deal, is vulnerable to being undermined not only by Iran but also by the United States; both have already raised eyebrows in the wake of the accord. Iran raced to produce uranium hexafluoride, a gas that can be enriched into bomb fuel, before it began to observe the temporary suspension on Monday. And both President George W. Bush and outgoing Secretary of State Colin Powell have publicly aired their suspicions that Iran will continue its drive for nuclear weapons under cover of the deal.

At the moment, administration hawks are pressing to confront the mullahs at the United Nations Security Council, where economic sanctions could be considered; calls for using force and for regime change are likely to follow.

Military action is inadvisable at this point, because of a dearth of solid intelligence and the secretive, geographically diffuse nature of Iran's nuclear sites. If the issue reaches the Security Council with the United States and Europe continuing along divergent paths, the inevitable deadlock will deal a severe and lasting blow to international security. Therefore, the agreement must be fortified to keep the Iranians honest, the Europeans effectively engaged and the U.S. hawks bridled.

This can be achieved through a U.S.-European accord laying out trigger mechanisms for specified consequences if Iran violates certain benchmarks. For example, if Iran fails to allow inspectors the access accorded by the Nuclear Nonproliferation Treaty's additional protocol--which Iran is provisionally observing pending ratification--or resumes enrichment and centrifuge-building activities, it could face severe economic sanctions, censure by the Security Council (necessitating cooperation from Russia and China), or in the event of hostility, a forceful response.

We don't know yet whether Tehran will play by the rules. The regime has mastered the art of behaving badly and then seeking rewards for getting back into line. To date, the Europeans have played into its hands, offering carrots for compliance without wielding sticks to punish violations.

Therefore, the Bush administration's apparent comfort with a military option can serve as an important deterrent against Iranian cheating, arming the EU3 agreement with teeth that it would not otherwise have. Iran desires economic incentives but does not yet desperately need them; without a credible threat of U.S.-backed sanctions imposed by the international community, the mullahs can simply decide one day that the restrictions have ceased to be worth their while, and break any deal as though it were merely a business contract.

For the United States, accepting the EU3's carrot-based approach (provided the benchmarks are added) will show the world that it still supports negotiated diplomacy and multilateralism, even in cases where military threats loom. Participating in this framework will also send a message to Iran that the United States is not ruling out renewed relations. This would resonate with the largely pro-American Iranian populace, who despise their regime and are seeking inroads to break free of it.

But if the United States instead presents itself as a unilateralist maverick, it will hinder its own interests; the only thing Iranians disdain more than the mullahs is outside meddling with their deeply nationalistic desire for self-determination. The more overtly hostile the United States acts toward Iran, the more the mullahs are able to spin America's posture to alienate Iranians against the "Great Satan."

The way to keep the Iranian regime in check while speeding its demise is to insure the nuclear agreement through benchmarks and triggers, and then give the mullahs exactly what they ask for in terms of increased access to international institutions like the World Trade Organization.

Such carrots can also be Trojan Horses, allowing the forces of democratic reform within Iran to blossom by enabling pro-democracy elements to make global connections. The U.S. and Europe should saddle up those horses together.

Nuclear weapons states must move to disarm, and nations must join in multilateral approaches to prevent further nuclear proliferation, said Mohamed ElBaradei, head of the International Atomic Energy Agency (IAEA), at CISAC's Drell Lecture on Nov. 4.

"If we are ever to build a global security culture based on human solidarity and shared human values -- a collective security framework that will serve the interests of all countries equally, and make reliance on nuclear weapons obsolete -- the time is now," ElBaradei said. Drawing lessons from Iraq and other recent experiences with IAEA nuclear weapons inspections, ElBaradei called upon politicians, scientists and society to join in international collective actions toward nuclear disarmament.

ElBaradei's lecture was covered by Reuters, the Stanford Daily: U.N. expert cites nuclear danger, the San Jose Mercury News and other news media.

Mohamed ElBaradei, director-general of the International Atomic Energy Agency (IAEA), will deliver the annual Drell Lecture, presented by the Center for International Security and Cooperation (CISAC), 4 p.m. Thurs., Nov. 4, 2004, in Stanford University's Kresge Auditorium. His lecture, "Nuclear Non-Proliferation and Arms Control: The Road Ahead," is free and open to the public.

As head of the IAEA, ElBaradei oversees international inspections enforcing provisions of the Nuclear Non-Proliferation Treaty (NPT) and related arms control agreements. Prior to the U.S.-led invasion of Iraq in spring 2003, ElBaradei and Hans Blix, former chief of U.N. Monitoring, Verification and Inspection Commission (UNMOVIC), the IAEA group charged with carrying out U.N. Security Council-mandated inspections in Iraq, reported progress with the inspections. As IAEA inspectors evacuated from Iraq on March 19, 2003, ElBaradei continued to urge completion of the U.N. Security Council inspection process.

More recently, IAEA reprimands of Iran have made headlines, with the agency's board of governors scheduled to revisit Iran's compliance with NPT provisions shortly after ElBaradei's visit to Stanford. On Sept. 13, 2004, the IAEA issued a deadline of Nov. 25 for Iran to report fully on its nuclear program. For more than a year, the U.S. has advocated referral of Iran's case to the U.N. Security Council, after inspections revealed evidence of covert Iranian nuclear research.

Before assuming the IAEA's top job on Dec. 1, 1997, ElBaradei held a number of high-level policy positions, including that of IAEA legal adviser. A diplomat and scholar, ElBaradei works closely with international organizations, particularly in the fields of peace, security and law.

CISAC's Drell Lecture traditionally addresses a critical national or international security issue that has important scientific or technical dimensions. The lecture is named for Sidney Drell, CISAC's founding science co-director. Albert and Cicely Wheelon generously endowed the lectureship.

I begin with a proposition. There are a great many pressing problems in the world. There is population growth and economic development, with attending pressures on resources - including food and that other essential, water. There is a continuing global security crisis, augmented by the rise in terrorism. There is the chronically inequitable distribution in resources between the rich nations of the North and the poor nations of the South. And there is the steadily growing body of evidence for a major reorganization of the global climate regime.

My proposition is that the last of these is the most serious threat - not only because it will profoundly affect the lives of our children and our grandchildren in a direct way, but also because it will interact powerfully with every single one of the other problems I have listed.

Let me begin with the science underlying climate change. Last week I helped organize a symposium and briefing session on climate science for press, policy-makers, and the public, supported by the Hewlett Foundation and with co-sponsorship from the Conference Board. We had ten of the most distinguished climate scientists in the United States, led off by Sherry Rowland, the Nobel Laureate in Chemistry. The purpose was to make a careful assessment of the science - what we know for sure, what we think likely, and what are interesting but unproven possibilities.

So here is a short summary of what we know. General Circulation Models - climate models that take into account variations in the sun's energy, volcanic activity, and other natural phenomena - explained fluctuations in average global temperature very well over most of the past thousand years. But for the past hundred years, these same models faithfully reproduce global temperature history ONLY if they include the greenhouse gases - carbon dioxide, methane, and chlorofluorocarbons - that are by-products of human economic activity. That is why the average temperature of the globe has risen by about one degree F, and the sea level has risen by between 10 and 20 cm., in the last century. The primary causative agent is carbon dioxide, which in preindustrial times was about 280 ppm/v and has now reached 380ppm/v. It is rising continually as the activities that produce it are proceeding on a business as usual basis. That is because the failure of the Kyoto protocol - a failure both because its targets were inadequate, and also because they were unattainable by many of the participating nations - has left us without any basis for meeting the goals of the 1992 Framework Convention on Climate Change. Just to remind us, the US is a signatory and a party to that agreement, under which we are committed to limit atmospheric concentrations of greenhouse gases to avoid "dangerous anthropogenic interference with the climate system."

Why, a dozen years later, is there some doubt about the dangers of this interference? The C02 we add to the atmosphere will stay there; its average residence time is a century. There is no disagreement about whether average global temperature will rise; it will. The scientific debate is about how much. For the future we depend again on the General Circulation Models. It's reassuring that when applied to past climates in "back-casting" efforts, like the example I gave a moment ago, these actually predict climate history so accurately. Perhaps more interesting, they regularly somewhat underestimate the magnitude of the real climate changes - that is, Nature regularly turns out to be harsher than the models suggest. Projecting the models into the future, the Intergovernmental Panel on Climate Change, and an evaluation by the National Academies prepared at President Bush's request, estimate that by the end of this century, the increase in average global temperature will be between 1.4 and 5.8 degrees Centigrade.

Why such a range? These models, like most, contain some uncertainties. Some of these are scientific: how increased cloud cover might affect the outcome, since clouds can either cool the climate by reflecting sunlight from above, or warm it by trapping heat that is leaving from below; how changes in the earth's albedo due to melting ice might accelerate heating, and so on. Aerosols produced by volcanic eruptions have a cooling effect, as the eruption of Mt. Pinatubo did in giving us two unusually cool years in the early 90's. Other uncertainties are economic and social: we don't know how national policies and international agreements will serve to restrain the amount of greenhouse gases we are adding.

These uncertainties - about half due to the models themselves, and the rest to social and economic unknowns -- have provided arguments for those who prefer to postpone economically difficult approaches for controlling greenhouse gas emissions. But it is important that even at the very lowest estimates, there will be substantial changes in the nature of human life on the only planet we currently occupy. The rather modest impacts of the past century have already produced profound changes in regional climate dynamics. Substantial ice-sheet melting and retreat is taking place both in the Arctic and in the West Antarctic ice sheet. In the Arctic, where climate warming has been extreme, sea ice is sharply diminished and rivers become ice-free much earlier. Low latitude mountain glaciers are shrinking; the famous snow-capped summit of Kilimanjaro will be bare within fifteen years, converting hundreds of old African safari shots into historic treasures.

Biological cycles are experiencing the effects of warming, with upward extensions of the range of Alpine flora and advances in the time of flowering or breeding by an average of 5 days per decade. The models have all also predicted more frequent and severe weather events, and we have had heat waves in the upper Midwest and Paris, accelerated beach erosion on coasts all over the world, and disastrous floods and landslides in Central America.

That is now, but of course we are more interested in the future. What the models tell us unambiguously is that the climate system is headed for further disruption. The standard scenario foresees a steady, ramp-like increase in average global temperature, with a concomitant rise in sea level, but records of past climate tell us that it is riddled with abrupt changes - something that the models fail to predict well. A possible alternative involves a change in major ocean circulation patterns - especially in the North Atlantic, where a clockwise gyre brings warm equatorial water up via the Gulf Stream. As it flows Northward and then crosses Eastward, it is cooled by the atmosphere, becomes more saline through evaporation, and then sinks to return as a cold deep current. If large discharges of fresh meltwater or rain made this water less dense, it could fail to sink and thus disrupt the entire cycle.

A fictionalized version of such a scenario appears in the disaster film "The Day After Tomorrow," which you should see only for amusement. Beyond that silliness lies a real prospect that a gradual change in average global temperature could intercept the threshold for some non-linear, dynamic process, triggering abrupt changes in either direction. Of course there is uncertainty: we are engaged in a large-scale, uncontrolled experiment on the only planet we have.

Let's consider some collateral impacts. A group of us at Stanford was asked by the Carnegie Commission on Preventing Deadly Conflict to look - among other things -- at ways in which environmental change might alter the circumstances under which human populations might be placed. Climate change was an important variable. One example we looked at was the impact of sea level rise, along with storm surges from extreme weather events, on the Ganges-Brahmaputra delta. Flood disasters already occur there regularly. 15 million people live within 2 meter above sea level, and are vulnerable to abrupt displacement. We know they will have to go somewhere; in the past they have fled in much smaller numbers to Bengal. The security problems arising from a massive influx of a traditionally hostile population, combined with an almost certain high level of cholera infection, are not difficult to imagine.

Water is a desperately important resource in most parts of the world, and drought is often followed by famine or emigration. Here in the US, warmer winters threaten mountain snowpacks and will soon demand the revision of interstate and international water allocation agreements. Maritime rivers are already undertaking management steps to deal with saline intrusions due to sea level rise or storm surges. In Great Britain, the barrier that protects London from occasional flooding of the Thames estuary is now being used six times a year compared to less than once a year in the 1980's.

Agriculture, of course, is the most essential of human activities. The regional distribution of global warming impacts may be at least temporarily kind to temperate-zone food production. But the models all predict an increased incidence of mid-continent droughts as climate change progresses, and we know that the American Midwest has in the past experienced droughts both deeper and longer than the one in the 30's that led to the Dust Bowl migrations. Irrigation is an answer to drought, but in the six High Plains states, dryland wheat production depends upon the Ogallala Aquifer, a buried ice-age storage well that is being so rapidly depleted that it is already unusable in its southern portion. And in the tropics, where people are poorest and capacity to adapt is minimal, the consequences of even modest warming will be far more serious.

Infectious diseases are spread by vectors, like the Anopheles malaria mosquito, that have their own patterns of reproduction, movement, and climate sensitivity. In parts of Africa where vertical topography dominates, warmer and rainier seasons cause malaria incidence to rise in higher-altitude locations. In a warmer and wetter world, more of the same can be expected.

So climate change is not an isolated problem. Instead, it is likely to interact with most of the other problems humans face all over the world. Thus I hope that this meeting will help encourage us to prepare a sound portfolio of risk-reducing measures. These will not, I must tell you, bring us out of the woods. Our destiny is partly built in -- to the heat that is already locked into our oceans, to the greenhouse gases that are already in our atmosphere and will increase by another 50% or more no matter what we do, and to the justified economic appetites of the developing world. What we will be talking about, it should be clear, are ways of limiting the damage to manageable levels, NOT preserving the status quo. We lost that years ago.

So the contemporary policy challenge amounts to a bet about risk: are the consequences of business as usual likely to entail costs greater than those of beginning to mitigate those consequences now? Other nations - the UK, several EU countries, and Japan - are making substantial commitments. Some industries - British Petroleum, Royal Dutch Shell, and Swiss Re, for example - have undertaken steps of their own. The insurance burden from the exploding rates of coastal erosion and storm damage has pushed the insurance industry to lead. If companies fail to participate in emissions reduction and join with others to resist such measures, questions are already being raised. If you believe so strongly that climate change is a myth, Swiss Re might say, then surely you won't mind a climate-related events exclusion from your Directors and Officers insurance policy.

But we can't count on voluntary actions, and the United States so far has only announced a long-range research program that, although it looks reasonable, makes NO current commitments to mitigate our contribution, about a quarter of the world's, to the global warming problem. We must have a more aggressive national policy to purchase insurance against this risk.

It will not be cheap. We have old, coal-fired power plants in this country; it may take subsidies to replace them with modern, less carbon-intensive facilities that run on natural gas. States like mine are already driving the transportation sector to ultra-low emission, and that may move the domestic industry in a positive direction. Some of us will have to give up our reflex opposition to nuclear power and begin comparing its risks realistically against those of global climate change. Although the room for alternative energy sources (photovoltaic, wind, geothermal) is limited, these options need encouragement. Energy conservation measures have, at several times in the past, turned economic predictions on their head by their success, and the right incentives could yield real benefits there.

The portfolio I have just described is needed, but will not be enough. We know that market-based mechanisms for emissions control can work, because they did in the 1990 Clean Air Act Amendments that limited SO2 emissions. The bill proposed by Senators McCain and Lieberman would mandate a cap-and-trade program for controlling carbon dioxide emissions. Similar systems are being considered by regional assemblages of states in the Northwest and the Northeast, and that may encourage the development of a national system - which could then build trading relationships with other nations that are moving toward similar regimes. A case for this approach is elegantly made in the Council on Foreign Relations Policy Initiative on Climate Change, by my colleague David Victor.

The United States is in a position of natural leadership here. It is the most powerful nation - and the world's leading producer of greenhouse gases. Plainly it is in its own national interest, in multiple ways, to reduce its consumption of fossil fuels. To see it failing in this most vital, globally sensitive matter is a national embarrassment.

In an address at the recent CISAC-sponsored Conference on South Asia and the Nuclear Future, held June 4-5 at Stanford, New York Times reporter David Sanger discussed the nuclear trading network of Abdul Qadeer Khan, which exported nuclear weapons and weapons components to some of the world's aspiring nuclear powers. Sanger's talk, "U.S. Responses to the A.Q. Khan Network," was based on a series of articles previously published in the Times, which resulted from his in-depth research and reporting in collaboration with other Times reporters.

In his talk, Sanger discussed how the Khan network began and how it worked; how it has made clear the limitations of the nuclear Nonproliferation Treaty; how it has raised serious questions about the quality of intelligence about nuclear proliferation; and how it has forced a fundamental rethinking of the nuclear danger posed to the world.

Mitchell Reiss, director of policy planning for the U.S. State Department, gave the keynote address for a recent CISAC-sponsored Conference on South Asia and the Nuclear Future, held June 4-5 at Stanford. Reiss discussed the major obstacles to peace and stability in India and Pakistan, the steps the Bush administration is taking to collaborate with and strengthen both countries, and the international community's role in promoting nuclear non-proliferation in the region.