Michael Gerson

WASHINGTON -- It is a political error for a candidate to believe that voters who agree with him will always end up supporting him.

There is little doubt that Americans generally feel that the initial use of military force in Iraq was a mistake. Recent, paradoxical polls show a dramatic increase in the number of people who believe that the war is now going well alongside a hardening majority who believe it should not have been begun at all. Barack Obama's strongest argument on Iraq is increasingly about the past.

But presidential elections tend to focus on the future. In spite of their past failures, whom do you trust more to conduct a flawed, messy war in the years ahead? Lincoln or McClellan? Nixon or McGovern? Bush or Kerry? McCain or Obama?

At some point, most foreign policy debates, especially during a war, come down to a binary determination: Is a candidate strong or weak? Voters can disagree with a nominee on many things and still find him stronger than his opponent.

So far, Obama has not taken this challenge with sufficient seriousness. His Iraq approach comes down to three points. First, he has voted twice against funding U.S. troops in the field -- a political necessity in the Democratic primaries, but a blunder with the broader electorate. No matter what subtleties Obama attempts to develop in his Iraq position, this will be seen as a symbol of impulsive radicalism, unbecoming in a commander in chief.

Second, Obama advocates a specific timetable for the withdrawal of American combat troops in order to pressure the Iraqi government to take its responsibilities more seriously. (In fact, according to Obama's January 2007 Iraq plan, all combat troops would already be out of Iraq.) But it seems increasingly unfair to denigrate the efforts of Prime Minister Nouri al-Maliki's government, which has moved forward on 12 of 18 benchmarks set by Congress, and has recently engaged Shiite militias in a fight the U.S. has been demanding. In many cases, the Iraqis seem to lack capacity, not will -- which is precisely Gen. David Petraeus' argument for continued American engagement.

Third, Obama promises to personally negotiate with President Mahmoud Ahmadinejad on Iran's destabilizing support and training of Shiite militias. What might seem a bold strategic maneuver from a Nixon or Kissinger smacks of dangerous naivete from a fourth-year senator.

Michael Gerson

Michael Gerson writes a twice-weekly column for The Post on issues that include politics, global health, development, religion and foreign policy. Michael Gerson is the author of the book "Heroic Conservatism" and a contributor to Newsweek magazine.
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