IT'S LEGACY time. As the Bush administration winds down, the race is on to shape how future generations will view the past eight years. The president himself seems keenly aware of the clock, declaring his intention to grab that most elusive brass ring, peace in the Middle East, before he leaves office. Former officials are not waiting that long, publishing memoirs about the Bush years before the Bush years are over. Former CIA chief George Tenet, top Justice Department official Jack Goldsmith, Pentagon policy chief Douglas Feith and White House Press Secretary Scott McClellan have all penned best-selling insider accounts in the past year. While some kiss and tell more than others, all seek to cast old events in a new light. Setting the record straight has become the most important and popular game in town.

So just what will the Bush foreign-policy legacy be? Over the past several months, I have put this question to more than a dozen leading academics and senior foreign-policy officials from the past three presidential administrations. What I found was surprising. Although the harsh judgments of Bush's performance will most likely endure, so too will his grandest foreign-policy idea: that democratizing the Middle East is the best way to combat the root causes of terrorism and the surest road to peace. For all the criticism of Bush's foreign policy, both John McCain (R-AZ and Barack Obama (D-IL) embrace the president's "freedom agenda." America's forty-third president may go down as one of the most criticized in American history, but his grand strategy will undoubtedly set the course of American foreign policy for the next administration, and possibly the next generation.

ALMOST NOBODY thinks the president is doing a good job. Bush continues to set public-opinion records-the bad kind. He has received the highest public-disapproval rating ever recorded by Gallup in its seventy-year history. He holds the second-worst approval rating ever (even lower than Richard Nixon's just before he resigned over the Watergate scandal). And 63 percent of Americans consider the Iraq War to be a "mistake." That's the highest recorded opposition to an active war in American history-and a full two points higher than peak opposition to the Vietnam War in May of 1971.

The current prevailing wisdom, expressed publicly by many Democrats and privately by many Republicans, is that democratizing Iraq and the rest of the Middle East is a costly long shot that has done great harm to America's standing and security in the world. William J. Perry, President Clinton's secretary of defense, told me, "I think they'll pay a very negative legacy on Iraq in two respects. First, imposing democracy without understanding the costs. Second, undertaking a war without adequate planning." Former-President Jimmy Carter was far less diplomatic, calling the Bush presidency the "worst in history." The late conservative icon William F. Buckley echoed disapproval across the aisle, declaring in 2006 that Bush was not a true conservative, that the Iraq War had failed so miserably that any European prime minister would be expected to retire or resign, and that the president would have no foreign-policy legacy at all. As one former Bush administration official recently lamented, "What can I say? It looks very bad."

Many inside the administration are counting on history-lots of it-to overturn this existing consensus. They believe that democratization will eventually come to the Middle East, and when it does, vindication will follow. In May, speaking on the sixtieth anniversary of Israel's independence, the president shared his vision of the world sixty years from now: in 2068, the Palestinian-Israeli conflict would be settled; Iran and Syria would be peaceful nations; terrorism would be soundly defeated; and democracy and free trade would flourish across the region "from Cairo to Riyadh to Baghdad and Beirut." Secretary of State Condoleezza Rice firmly believes that this ambitious vision is attainable. As she told me in June, international politics is filled with outcomes that seemed unimaginable beforehand and inevitable afterward. She recited with ease what she called the "list of horrors" that confronted President Truman after World War II: raging civil conflicts in Greece and Turkey, 2 million starving Europeans, large Communist electoral gains in Italy and France ("The question," she noted, "wasn't will Eastern Europe go Communist. It's will Western Europe go Communist?"), a permanently divided Berlin, war in the Middle East, a Communist coup in Czechoslovakia, a Communist revolution in China, the explosion of a Soviet nuclear weapon five years ahead of Western predictions and the outbreak of the Korean War. "Is there any way to figure," she asked rhetorically, "that in 1989, 1990 and 1991, Eastern Europe is going to be liberated, Germany is going to be unified on Western terms and the Soviet Union would be no more? Or that South Korea would have the eleventh-largest economy in the world? That France and Germany were never going to fight again? That in 2006 you're going to hold a NATO summit in Latvia?" It is a lesson worth remembering. As Nobel Laureate economist Thomas Schelling once cautioned, "There is a tendency . . . to confuse the unfamiliar with the improbable."

Yet even if Bush's hopeful vision of 2068 becomes reality, judgments of his presidency are not likely to change. Two reasons explain why. First, history more often magnifies than reverses. As years pass, memories fade and vital details are forgotten. All of the complexities and uncertainties swirling around the president and his aides in the moment dissipate and determinism sets in. In hindsight, policies are seen as either brilliant and inevitable (President Kennedy's choice of a naval blockade during the Cuban missile crisis) or colossally stupid (President Carter's aborted rescue mission of American hostages in Iran). In reality, both decisions were vigorously debated. And both were a hair's breadth away from turning out differently. Had Kennedy made his decision on the first day of the crisis rather than the seventh, the United States would have launched an air strike against Soviet missiles in Cuba that could have triggered thermonuclear war. Had one helicopter pilot continued flying to Tehran when a notoriously unreliable warning light went on (the gauge had falsely indicated rotor-blade malfunctions forty-three times before), Carter would have given the rescue mission a green light, which could have altered the course of U.S.-Iranian relations and the 1980 presidential election. But these contingencies get lost with time. Yogi Berra once said that predicting is hard, especially about the future. In foreign policy, predicting the past is even harder.

Harry Truman's presidency illustrates the lasting impact of first impressions. For many Bush officials, Truman is a comforting role model-another wildly unpopular wartime leader who aimed big and is now viewed as one of the presidential greats. As Rice reflected, "When you're at the beginning of a big historical transformation, it doesn't look like you're doing much right." Bush himself invoked Truman at his 2006 West Point graduation speech, comparing the struggle against Communism to the war against Islamic radicalism and noting that "Like Americans in Truman's day, we are laying the foundations for victory." No one disputes that Bush's aims are sweeping or that, like Truman, he seeks to transform international relations for a new enemy in a new era. Bush's second inaugural proclaimed American foreign policy to be nothing less than spreading "democratic movements and institutions in every nation and culture, with the ultimate goal of ending tyranny in our world." The difficulty of the task, he said, "is no excuse for avoiding it." Ending tyranny would be "the concentrated work of generations." As Rice noted, the president does not just defend the status quo.

When it comes to vindication, however, the Truman parallels fall short. History's judgment of Harry Truman came early, not late. His greatest cold-war policies were recognized as triumphs from the start, and his failures remain failures to this day. Truman's March 1947 containment speech to Congress was met with a standing ovation and press reports that instantly hailed it as a historic landmark in U.S. foreign policy. His European economic-recovery program, the Marshall Plan, also attracted widespread public support (thanks in large part to the administration's own public-relations campaign) and produced impressive and fast results. In 1953, just five years after it began, the Marshall Plan formally ended, Europe was well on its way to economic recovery and Secretary of State George Marshall received the Nobel Peace Prize for his work. At the same time, history has not reversed judgment about Truman's foreign-policy failures. Nixon may have opened China, but Truman still lost it. For starving North Koreans or anyone who worries about Kim Jong-il's nuclear weapons and crackpot tendencies, the Korean War is still searching for a happy ending.

Truman, like Bush, did face stormy opposition and plummeting public approval during his presidency. But his low popularity had many causes, and foreign policy was not the primary one. Postwar economic reconversion, high taxes, government spending, labor disputes, the firing of General Douglas MacArthur, the anti-Communist hearings of Senator Joseph McCarthy and salacious corruption scandals including influence peddling with fur coats and deep freezers all helped to sour the public's mood by 1952. In January, Truman's public disapproval hit a whopping 67 percent, a record surpassed only by the current president. Notably, the same poll asked Americans what they believed were the most important issues in the 1952 presidential election. More said government waste and corruption than the Korean War. Republican Party leaders agreed, ranking corruption and wasteful government spending their top two campaign issues by overwhelming margins in a November 1951 Gallup poll. The Korean War ranked a distant fourth (behind taxes), and other foreign issues were even lower. Domestic policy, not foreign policy, was the administration's greatest weakness and the Republicans' best hope. Combating the "mess in Washington" became one of Dwight D. Eisenhower's central campaign themes. The Republican presidential nominee made headlines and scored one of the biggest ovations of the campaign when he assailed the Truman administration as "barefaced looters" during an Indianapolis stump speech. The notion that Truman was drummed out of office for foreign-policy failures that were subsequently judged successes might be comforting, but it is not correct.