The carnage and chaos that have wracked Rwanda and Haiti in recent months would seem to be unrelated, sparked by distinctly different ethnic or political rivalries in sub-Saharan Africa and the Caribbean.
Could each country be the victim of a common underlying malady, one that has fanned long-standing tensions into conflict? Consider:
Before massacres and mass exodus depopulated Rwanda, the Maryland-sized nation had more people per square mile than almost any other African country, and declining food production. With each woman of child-bearing age having more than eight children, it also had one of the highest fertility rates.
In Haiti, where 7 million people are crammed into a similarly small area, the economy is in shambles and the land badly deforested. With a fertility rate of nearly five children per woman, the country's population is projected to double in just 18 years.
"Resource scarcities are a root cause of the violent conflicts that have convulsed civil society" in countries like Rwanda and Haiti, asserts Timothy E. Wirth, U.S. undersecretary of state. Such conflicts could intensify and widen, he adds, "as ever-growing populations compete for an ever-dwindling supply of land, fuel and water."
Thus, in a major policy switch from previous Republican presidencies, the Clinton administration is pushing for an international commitment to slow the world's surging population growth at a coming United Nations conference in Cairo, Egypt.
"Current conflicts are a grim foreshadowing of the anarchy that could engulf more and more nations if we fail to act," Mr. Wirth warns. Nor would the United States be immune, he adds, noting that "environmental devastation and disease do not stop at national borders."
When they gather in Cairo Sept. 5, delegates from the world's nations are expected to act on a plan intended to stabilize global population at 7.8 billion by 2050. Unless something is done, U.N. planners predict, today's 5.6 billion people could more than double, to 12.5 billion, by that time.
In a draft "program of action" hammered out earlier this year, the United States and most other nations have agreed that the the best way to stabilize population is to provide more family planning and contraceptives, and to enhance women's education, employment and political rights.
But the U.N. plan is generating its own conflict. Pope John Paul II and the hierarchy of the Roman Catholic Church charge that the policy statement promotes abortion on demand and homosexuality. Church leaders also have accused drafters of "cultural imperialism" and of sanctioning sexual promiscuity in pushing for wider access to contraceptives.
Moreover, some church leaders and others have questioned whether population growth is a problem at all. The Pontifical Academy for Life, an arm of the Catholic church, decried "the alarmist campaign," pointing out that "the so-called 'demographic explosion' is actually subsiding" and some countries -- notably Russia and some in Western Europe -- are even experiencing declines in population.
Few issues have sparked more intense debate than how many people the Earth can support.
Long before the English cleric Thomas Malthus earned lasting fame for his gloomy predictions in 1798, thinkers were worrying about whether the land could support all the people on it, says Joel Cohen, a population expert at Rockefeller University in New York.
But for the last 50 years, the question has taken on increasing urgency, as world population grew at a record pace. After reaching 2 billion during the 1930s, global population growth has mushroomed to where another 1 billion people are being added every 10 years.
That increase -- roughly 10,000 new people every hour -- is akin to populating another Baltimore City every 36 hours, another New York City every month or another country the size of Mexico every year.
Environmentalists and economists hotly debate whether population growth is a bane or boon to nations that are struggling to get out, or stay out, of poverty.
The world's swelling ranks represent "a triumph of human knowledge and organization over the raw forces of nature," argues Julian L. Simon, professor of business and management at the University of Maryland College Park and a widely quoted optimist on population matters. As the landscape becomes more crowded, people will figure out how to solve whatever problems or shortages might arise.
Dr. Simon maintains that "there is no statistical evidence to show population growth has negative effects" on human welfare or the environment. "Every single trend in human welfare shows improvement in the long run," he says.