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.

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.

We've been down this road before: A crisis threatens global security, and the international community is not coming together to deal with it. Hawks in the U.S. administration see the Europeans as too timid to use force and reliant on diplomacy to a fault, while many Europeans see the United States as trigger-happy and too impatient with negotiated settlements. This lack of cohesion damaged the legitimacy of the American-led war in Iraq and left U.S.-European relations in tatters. A similar disunity jeopardizes current attempts to manage Iran's nuclear aspirations, even though both sides agree that the threat posed by a nuclear Iran is grave and real.

Departing Deputy Secretary of State Richard L. Armitage positively spun the divergent U.S. and European approaches to Iran: "The [diplomatic] incentives of the Europeans," he said, "only work against the backdrop of the United States being strong and firm on this issue. In the vernacular, it's kind of a good cop/bad cop arrangement. If it works, we'll all have been successful." The problem with Armitage's hopeful outlook is that the good cop/bad cop strategy works only if pursued consciously and in coordination, and the U.S. and European approaches do not reflect that yet. In fact, they seem headed in opposite directions.

The good cops--Britain, France and Germany--recently persuaded Iran to suspend all uranium enrichment-related activities until they reach a final accord. If the mullahs cooperate, they will receive numerous economic carrots, including possible membership in the World Trade Organization (the U.S. would have to agree) and improved trade relations.

In October 2003, when the International Atomic Energy Agency was prepared to take its negative report on Iran's nuclear program to the U.N. Security Council, the mullahs cut a similar deal with the Europeans, promising to suspend all enrichment-related activities. But Iran soon grew impatient with the agreement and resumed efforts to produce the gas that feeds uranium enrichment. It similarly rushed to make as much of that gas as possible before the latest accord's deadline, undercutting confidence in the deal on both sides of the Atlantic. In another bad-faith move, Iran announced last week that it wanted to keep operating uranium-enrichment equipment for research purposes, backing off its pledge to freeze all such activities.

Enter the bad cop--the United States. It has pushed to refer the question of Iran's nuclear aspirations to the Security Council. When Secretary of State Colin L. Powell steps down, the hawkish voices in his department will probably intensify and gain influence, especially if the mullahs break the newest deal.

Armitage might be right that the discordant U.S.-European approaches will push the mullahs to hold to the deal. But the U.S. will be uncomfortable with an agreement that does not insist on any means of enforcement or verification, as is the case with the latest accord.

Iran knows that the war in Iraq colors U.S. conduct toward it. The worse Iraq gets, the less Iran worries--and the mullahs don't seem too worried at the moment. But if they break the accord with the Europeans and the Europeans respond timidly and U.S. resources are freed up as a result of an improving situation in Iraq, the U.S. could take on Iran alone--to everyone's detriment. To avoid this risk, the U.S. and Europe need to harmonize their approaches and develop a coordinated strategy for Iran. The best way to accomplish this is to agree in advance on the consequences Iran will face if it violates its commitments. For example, if the mullahs renege on the latest deal, frustrate the monitoring and verification efforts of IAEA inspectors or fail to ratify an addition to the Nuclear Non-Proliferation Treaty that allows for more invasive inspections, the U.S. and Europe should go to the Security Council, impose economic sanctions or, in the worst case, take military action.

Fortunately, diplomatic disunity over Iran does not run as deep as it did over Iraq, where even the nature of the threat was a bone of contention. Both the U.S. and Europe are worried about a nuclear Iran, and they feel strongly about enforcing the rules of nonproliferation. In June 2003, European foreign ministers required only 45 minutes to approve a document that endorsed U.N.-sanctioned use of force as a last resort against proliferators, as well as "political and diplomatic preventative measures."

If the Europeans agree to leave all responses on the table and to act decisively at the first sign of Iranian mischief, the United States would be foolish not to form a partnership with them. (It's also important that the U.S. set a better example as a member of the nonproliferation community by abandoning plans to build new mini-nuclear weapons and ratifying the Comprehensive Test Ban Treaty.)

The role the U.S. forges for itself in dealing with Iran will have significance beyond reinvesting in international order or responding to the mullahs' nuclear ambitions. Iran's despotic regime will collapse some day, and there will be a "morning after" similar to that in Iraq, where reconstruction efforts have floundered because U.S. planners underestimated the challenge of nation-building and the need for international support to make it work. When Iran makes its move toward a better government, the U.S. should be in a position to lead a coherent, collective international effort to help it get off the ground.

Yet since the severing of U.S.-Iranian ties in 1980, the U.S. has been slack in developing a viable Iran policy. Iran's nuclear ambition should be motive enough to reverse this inattention. U.S. policy toward Iran must cease to be reactive, as it is now.

In addition to working with the Europeans to curb the mullahs' nuclear efforts, the U.S. should begin crafting a strategy to work toward--and then with--a democratic Iran. Supporting a government that complies with its international obligations is certainly preferable to containing one that thwarts them. By getting involved now, the U.S. can do much to show Iranians that it will be a friend to a free Iran. A democratic Iran may still want a nuclear bomb as a matter of national pride. But a less threatening, pro-diplomacy U.S. would be in a stronger position to argue the benefits of membership in the nonproliferation community rather than life as a rogue power.

Participating in a multilateral approach to Iran's nuclear program is a great place to start. In doing so, the U.S. will signal to Iranians that its aggressive position does not reflect a desire to remake Iran in its own image but rather a desire to achieve, alongside Europe, a substantial victory for nonproliferation and international security.