Imagine that there was just a snowstorm up in Vermont, that the ski conditions are spectacular, that you have no plans or commitments for the weekend, and that your friends are all clamoring for a ski trip. Under these circumstances, you might very well decide to hop in the car and start driving north to ski country. But what if it recently rained, the ski slopes are full of bare patches, and you have a major paper due the Monday after your potential trip? Would you still go skiing that weekend? Probably not. But under the rules that presently govern American political discourse, changing your mind about your ski trip would lead commentators to dub you “unprincipled,” a “waffler,” someone who “flip-flops” on the issues that matter. On the other hand, going skiing despite the rain and rocks would likely inspire fawning coverage of your “courage” and “steady leadership in a time of change.”

At the current political moment, it’s clear which presidential candidate would go skiing regardless of the changed circumstances, and which candidate would evaluate the new facts and change his mind. President Bush’s adherence to his policies — even when the factors that once led rationally to the policies’ formulation now scream against their execution — is the hallmark of his presidency. Take Iraq, for instance. As Richard Clarke testified last week, to devastating effect, Bush entered office determined to invade Iraq and oust Saddam Hussein from power. Why? Because Iraq was believed to possess weapons of mass destruction, to be involved in international terrorism, and to pose a significant threat to American interests. But when all these factual predicates turned out to be false — when U.N. inspectors failed to find the faintest trace of any banned weapon, and the CIA told the president over and over again that Iraq was not linked to al Qaeda — did Bush’s position evolve? Not in the slightest, which is why America now finds itself bereft of allies in Iraq, and unable to defend its justifications for war.

The same obstinacy is evident in Bush’s approach to fiscal policy. As a candidate, Bush proposed a tax cut that reflected the realities of the late 1990s: a soaring stock market, a swelling budget surplus, and a relatively tranquil international environment. As Bush took office, though, the stock market was stagnating, surplus projections were already shrinking, and Sept. 11, 2001, soon created the most turbulent foreign policy situation in decades. But did Bush change his tax cut in response to the radically altered circumstances (say, by reducing its total size, or shifting its focus from long-term structural reform to short-term stimulus)? Again, no, which is the main reason why America now faces massive deficits as far as the eye can see.

Senator Kerry, of course, takes the opposite tack — freely changing his policy stances when the facts that motivated those stances have also changed. For example, he voted for the October 2002 Congressional Resolution authorizing the use of force in Iraq, but then criticized the president’s decision to initiate hostilities. Why? Because, as was clear in March 2003 but not in October 2002, Iraq’s weapons programs were an insignificant threat to U.S. interests, and the expected international consensus in favor of action had failed to materialize. Kerry also once opposed the death penalty without exception, but would now subject terrorists to capital punishment. Why? Because the events of Sept. 11 showed that terrorism is more akin to war, where death may always be visited upon one’s adversary, than conventional criminal activity. And Kerry voted for the Patriot Act, but now calls for its drastic overhaul. Why? Because when it was passed, legislators focused on the bill’s intelligence-sharing provisions, and could not have anticipated the insidious consequences it would have for civil liberties.

Kerry’s detractors gleefully dub these shifts in position as “flip-flops.” (The Republican National Committee even has a “Kerry v. Kerry” boxing game on its Web site, highlighting what Kerry once said on various issues compared to what he says now.) But I would argue that Kerry’s modified policy stances are not the product of indecision or political opportunism — but rather the rational response of an intelligent man to a changing world. Fundamentally, Americans must decide in this election what style of leadership is appropriate in an environment where unsettling new facts emerge daily, and long-held assumptions are constantly challenged. Do we want a president who ignores changes in circumstances, or one who embraces them? A president whose policies are rooted in ideology, or one whose recommendations are grounded in reality? I, for one, will cast my vote in November for the rule of reason. I want a president who is not afraid to change his mind about that ski trip when the rain starts to fall.

Nicholas Stephanopoulos is a first year student at Yale Law School. His column appears on alternate Mondays.