The fierce debate on immigration ignores a crucial reality -- what is happening to the United States is only one piece, although a big one, of a much larger global picture.

That hit me a couple of weeks ago when I was in Singapore. The Southeast Asian island nation has long been hailed as an economic model, the business capital for the entire region.

But it is an economy facing demographic peril. Its small population of 4 million is shrinking, thanks to a very low fertility rate. Prosperous Singaporean couples work hard, have fewer children and worry about how to take care of their aging parents. By 2050, Singapore will have a median age of over 52, one of the oldest in the world.

Singapore's answer is to import labor. A third of its workforce are migrants, from construction workers to maids. One out of seven households employs a domestic worker -- low-paid women mostly from neighboring Philippines and Indonesia.

Singapore tries to lure "talents'' -- highly skilled and affluent migrants -- to stay permanently. But the men hauling bricks and the maids washing laundry are in a separate class of temporary guest workers, with no chance to join Singaporean society. If a maid becomes pregnant, she is shipped out within seven days. Employers have to post bonds that must be paid should their servants break the rules and try to stay, putting them in the role of migrant police.

Problems of abuse of domestic workers, including physical and sexual violence and confinement, are serious enough to have prompted a report last December by Human Rights Watch.

Singapore's dependence on migrant labor and its guest-worker policy may be at the extreme end but it's very much on the global spectrum. Labor, like capital and goods before it, is part of a global market. The movement of people across borders in search of wages and work, most of it from developing countries to developed, is growing at a phenomenal pace.

The numbers are staggering. From 1980 to 2000, the number of migrants living in the developed world more than doubled from 48 million to 110 million. Migrants make up an average 12 percent of the workforce in high-income countries. About 4 million migrants cross borders illegally every year.

The demand for labor is driven in part by a demographic disaster -- the falling birth rates of developed countries. Almost all of those countries now have fertility rates that are well below 2.1, the level at which a population replaces itself. At the very low end are Hong Kong (0.94), Korea (1.22) and Singapore in Asia (1.24), along with much of Eastern Europe.

Low fertility means shrinking workforces and aging populations. Without migration, according to a recent study, Europe's population would have declined by 4.4 million from 1995 to 2000. Immigration accounted for 75 percent of U.S. population growth during the same period.

This movement of people cannot be stopped, certainly not by hundreds of miles of fences or even by tens of thousands of border guards. It is an issue that cries out for global cooperation, for common policies that cut across national boundaries. Already, we can benefit from looking at what has worked -- and not worked -- elsewhere.

A Global Commission on International Migration, formed in 2003 by the United Nations secretary-general, has taken an initial stab. Their report, issued last winter, supports the growth of guest-worker programs.

The Senate immigration bill now up for debate includes a provision for a guest-worker program. The bill is clearly preferable to the punitive and ineffective approach of the House version. But the Singapore experience -- and previous guest-worker programs like the German import of Turks -- should prompt second thoughts about going down this road.

One problem is that the guests don't leave. The United States has its own experience with this in the bracero program to import farmworkers, and more recently with the supposedly temporary H1-B visas used so extensively by the high-tech industry here in Silicon Valley.

Most troubling to me, these programs create an underclass of migrants who are never assimilated, as happened in Germany. It sets us on the Singapore road, encouraging inhumane policing mechanisms. And it is a gilded invitation to employers to depress the wages and incomes of American workers, and not just in the dirty jobs that are supposedly so hard to fill.

The United States has been rightfully proud of a tradition that treats all immigrants as citizens in the making. Rather than guest workers, isn't it more American to set realistic immigration quotas and enforce them fairly?

This past autumn the Freeman Spogli Institute for International Studies (FSI) in conjunction with the Woods Institute for the Environment launched a program on Food Security and the Environment (FSE) to address the deficit in academia and, on a larger scale, the global dialogue surrounding the critical issues of food security, poverty, and environmental degradation.

"Hunger is the silent killer and moral outrage of our time; however, there are few university programs in the United States designed to study and solve the problem of global food insecurity," states program director Rosamond L. Naylor. "FSE's dual affiliation with FSI and the new Stanford Institute for the Environment position it well to make significant steps in this area."

Through a focused research portfolio and an interdisciplinary team of scholars led by Naylor and CESP (Center for Environmental Science and Policy) co-director Walter P. Falcon, FSE aims to design new approaches to solve these persistent and under-prioritized problems, expand higher education on food security and the environment at Stanford, and provide direct policy outreach.

Productive food systems and their environmental consequences are at the core of the program. While many of these systems are global in character, but they are influenced significantly by differing food objectives, income level, and instruments among nations. The program thus seeks to understand the food security issues that are of paramount interest to poor countries, the food diversification challenges that are a focus of middle-income nations, and the food safety and subsidy concerns prominent in richer nations.

Chronic hunger in a time of prosperity

Although the world's supply of basic foods has doubled over the past century, roughly 850 million people (12 percent of the world's population) suffer from chronic hunger. Food insecurity deaths during the past 20 years outnumber war deaths by a factor of at least 5 to 1. Food insecurity is particularly widespread in agricultural regions where resource scarcity and environmental degradation constrain productivity and income growth.

FSE is currently assessing the impacts of climate variability on food security in Asian rice economies. This ongoing project combines the expertise of atmospheric scientists, agricultural economists, and policy analysts to understand and mitigate the adverse effects of El Niño-related climate variability on rice production and food security under current and future global warming conditions. As a consequence of Falcon and Naylor's long-standing roles as policy advisors in Indonesia, models developed through this project have already been embedded into analytical units within Indonesia's Ministry of Agriculture, the Planning Ministry, and the Ministry of Finance.

"With such forecasts in hand, the relevant government agencies are much better equipped to mitigate the negative consequences of El Niño events on incomes and food security in the Indonesian countryside," explain Falcon and Naylor.

Food diversification and intensification

With rapid income growth, urbanization, and population growth in developing economies, priorities shift from food security to the diversification of agricultural production and consumption. "Meat production is projected to double by 2020" states Harold A. Mooney, CESP senior fellow and an author of the Millennium Ecosystem Assessment. "In China alone, meat consumption has more than doubled in the past generation." As a result, land once used to provide grains for humans now provides feed for hogs and poultry.

These trends will have major consequences on the global environment-affecting the quality of the atmosphere, water, and soil due to nutrient overloads; impacting marine fisheries both locally and globally through fish meal use; and threatening human health, as, for example, through excessive use of antibiotics.

An FSE project is looking at these trends as it relates to intensive livestock production and assessing the environmental impacts to gain a better understanding of the true costs of this resource-intensive system. A product of this work recently appeared as a Policy Forum piece in the December 9, 2005, issue of Science titled "Losing the Links Between Livestock and Land".

Numerous factors have contributed to the global growth of livestock systems, lead author Naylor notes, including declining feed-grain prices, relatively inexpensive transportation costs, and trade liberalization. "But many of the true costs remain largely unaccounted for," she says. Those costs include destruction of forests and grasslands to provide farmland for corn, soybeans, and other feed crops destined not directly for humans but for livestock; utilization of large quantities of freshwater; and nitrogen losses from croplands and animal manure.

Naylor and her research team are seeking better ways to track all costs of livestock production, especially the hidden ones related to ecosystem degradation and destruction. "What is needed is a re-coupling of crop and livestock systems," Naylor says. "If not physically, then through pricing and other policy mechanisms that reflect social costs of resource use and ecological abuse."

Such policies "should not significantly compromise the improving diets of developing countries, nor should they prohibit trade," Naylor adds. Instead, they should "focus on regulatory and incentive-based tools to encourage livestock and feed producers to internalize pollution costs, minimize nutrient run-off, and pay the true price of water."

Looking ahead

The future of the program on Food Security and the Environment looks bright, busy, and expansive. While a varied portfolio of projects is in line for the upcoming year, a strong emphasis remains in the area of food security. Building on existing research at Stanford, researchers are identifying avenues for enhancing orphan crop production in the world's least developed countries-crops with little international trade and investment, but with high local value in terms of food and nutrition security. The work seeks to identify advanced genetic and genomic strategies, along with natural resource management strategies, to improve orphan crop yields and stability, enhance crop diversity, and increase rural incomes through orphan crop production.

Another priority area of research centers on the development of biofuels. Biofuels are becoming increasingly a part of the policy set for world food and agriculture. As countries such as the United States seek energy self-reliance and look for alternatives to food and feed subsidies under WTO (World Trade Organization) rules, the conversion of corn, sugar, and soybeans to ethanol and other energy sources becomes more attractive. New extraction methods are making the technology more efficient, and crude oil prices at $60 per barrel are fundamentally changing the economics of biomass energy conversion. A large switch by key export food and feed suppliers, such as the United States and Brazil, to biofuels could fundamentally alter export prices, and hence the world food and feed situation. A team of FSE researchers will assess the true costs of these conversions.

The FSE program recently received a grant through the Presidential Fund for Innovation in International Studies to initiate new interdisciplinary research activities. One such project links ongoing research at Stanford on the environmental and resource costs of industrial livestock production and trade to assess the extent and rate of Brazil's rainforest destruction for soybean production. "Tens of millions of hectares of native grassland and rainforest are currently being cleared for soybean production to supply the global industrial livestock sector," says Naylor. A significant share of Brazil's soybeans is being shipped to China, where rapid income growth is fueling tremendous increases in meat consumption."

A team of remote-sensing experts, ecologists, agronomists, and economists will be looking at the ecological effects on the landscape through biogeochemical changes and biodiversity loss, the impacts of land clearing on the regional hydrologic cycle and climate change, the economic patterns of trade, and the role of policies to achieve an appropriate balance between agricultural commodity trade, production practices, and conservation in Brazil's rainforest states.

"I'm extremely pleased to see the rapid growth of FSE and am encouraged by the recent support provided through the Presidential Fund for Innovation in International Studies," states Naylor. "It enables the program to engage faculty members from economics, political science, biology, civil and environmental engineering, earth sciences, and medicine-as well as graduate students throughout the university-in a set of collaborative research activities that could significantly improve human well-being and the quality of the environment."