By Peter J. Spiro

Let's say Barack Obama had been born in Kenya. Why wouldn't we still want him to be our president?

The recent surge in fringe chatter about Obama's eligibility for the presidency has no basis in fact. Obama was born in the state of Hawaii and thus meets the constitutional requirement that the president be a "natural born citizen."

Apparently seeking to harness some political advantage by playing to the so-called birther constituency, a group of Republican congressmen has sponsored legislation that would require presidential candidates to provide a birth certificate to the Federal Election Commission to establish eligibility.

The bill doesn't purport to define natural born, however. That's no easy task, and it should not be left to the bureaucracy.

The outrage among birthers has been fueled partly by a quirk in the history of citizenship law. If Obama had been born in Kenya, he would not have been a citizen at birth by virtue of his American mother. His mother, then 18, would have fallen short of the requirement that a citizen parent has been a U.S. resident for five years after her 14th birthday. (The requirement was shortened to two years for children born after 1986.) Obama's mother would have been able to bring him into the United States as an immigrant, five years after which he would have been eligible for citizenship.

What about John McCain's case? Even though McCain was born to American parents in the U.S.-controlled Panama Canal Zone, he may not have been a natural-born citizen because of an even more obscure legal technicality. (A legislative fix just before McCain's first birthday declared children born to American parents in the Canal Zone to be citizens at birth.)

There are other gray areas. Foreign-born adopted children are extended citizenship automatically upon admission into the United States with their new parents. Can any of the thousands who have moved here as infants from China, Korea, Guatemala, or Romania grow up to be president? Even if the circumstances of their birth can't be shoehorned into the constitutional language, there's a strong argument that they should be eligible.

And then there are the more than 15 million naturalized Americans who more clearly fall short of being natural-born citizens - among whom Obama might have been counted if the details of his mother's life were a little different. For them, the presidential eligibility clause represents sanctified discrimination, a kind of asterisk next to the principle that they enjoy equality with other citizens.

The Obama citizenship (non)controversy should be used not to better define arcane constitutional language, much less to impose filing requirements for the presidency. Rather, it's an opportunity to get rid of the birth requirement altogether.

The natural-born provision is an artifact of a time when one's birthplace was fraught with consequences. In the feudal conception of natural law, one was born into the protection of a territory's sovereign, for which one was thought to owe an indissoluble duty of allegiance. The framers of the Constitution worked in an era when such bonds were taken seriously. It made sense, then, to protect against a sleeper at the top.

Today, birthplace is hardly so meaningful. Many more individuals are being born outside the United States to U.S. citizen parents (often with dual citizenship), and others are naturalizing at an early age and maturing as Americans in every sense. Notions of perpetual allegiance dissipated long ago.

At the same time, the natural-born condition bars those who might well be among the best-qualified for the office. Obama would be no less fit for the presidency if he had been born in his father's homeland, and yet that accident of birth would have deprived the electorate of the opportunity to choose him.

Recent efforts to repeal the natural-born prerequisite by constitutional amendment were spearheaded by Republicans looking to clear a path to the presidency for Austrian-born Arnold Schwarzenegger. Utah Republican Orrin Hatch introduced the "Equal Opportunity to Govern Amendment" in 2003, and it enjoyed bipartisan support, including that of Michigan's Canadian-born Democratic governor, Jennifer Granholm.

But constitutional amendments require extraordinary political energy: a two-thirds vote of both houses of Congress and ratification by three-quarters of the state legislatures. No one has been willing to spend that sort of political capital on an issue that never seems urgent until it gets partisan.

Of course, it would take even more political fortitude to take up the amendment in the face of the birther crusade. Calling for repeal of the natural-born requirement now might be taken as a concession that there's something to the claim that Obama was not born in the United States.

But why not call the birthers' bluff? Their underlying nativist premise is that anyone not born a citizen should be forever disqualified from the presidency. It's time to make all American citizens eligible to run for and serve as president.

Peter J. Spiro is a professor of law at Temple University and the author of "Beyond Citizenship: American Identity After Globalization" (Oxford University Press). He can be contacted at pspiro@temple.edu.