WASHINGTON, 16 April 2004 — This has been a rough time for Americans. Just a year ago, Americans and Iraqis triumphantly pulled down the statue of Saddam Hussein in Baghdad. A year later, a spreading anti-American insurgency ripped across Iraq, accompanied by Iraqi mobs mutilating dead Americans and shouting hatred of the occupiers. An American year of miscalculations and misjudgments seems to have led Iraq into a chaos bordering on anarchy.

Sen. Kennedy’s crisp assertion — “Iraq is George Bush’s Vietnam’’ — crystallizes emotions in the United States and stirs powerful memories. “Failure is not an option’’ had been a favorite Pentagon cliche, but Pat Buchanan, an isolationist of the old school, now declares, “what Fallujah and the Shiite attacks tell us is that failure is now an option.’’ A respected professional diplomat Morton Abramowitz, asks “Does Iraq Matter?’’ in The National Interest, a sober conservative journal. “America’s pre-eminent power position in the world,’’ Ambassador Abramowitz argues, “can endure an early withdrawal from Iraq. US forces are so overstretched that a withdrawal might enhance our overall power position and our capacity to do more about Osama Bin Laden and other terrorist groups.’’ After all, did US withdrawal from Vietnam seriously undermine the American position in the world? Vietnam and Iraq are dissimilar in vital respects. In Vietnam we Americans inserted ourselves in an ongoing civil war; in Iraq we imposed war on the country for reasons that turned out to be false. But Vietnam and Iraq are indeed similar in the “quagmire’’ effect — and in the lack of historical experience and cultural knowledge and the consequent ignorance and arrogance that lead us into quagmires.

Of course 2004 is the year when Americans indulge in the quadrennial ritual of electing a president. The situation today is that roughly 45 percent of the electorate, according to most polls, love George Bush; and roughly 45 percent loathe him. Most of the 90 percent have made up their minds and are unlikely to change their votes.

But will not the war be the decisive issue? It is, after all, President Bush’s war. There was no popular clamor for a war against Iraq. If we had not gone to war, few Americans would have cared. Few would even have noticed.

Why was President Bush, as both Richard Clarke and the former Secretary of the Treasury Paul O’Neill have testified, so obsessed with Iraq? I do not think it is for petty reasons. Bush very likely buys into the neoconservative fantasy that the victory of democracy in Iraq will democratize the entire Islamic world and establish his own place in history. “A free Iraq,” as President Bush said on Tuesday, “will stand as an example to reformers across the Middle East.” Other reasons — oil, Israel, the search for military bases in place of Saudi Arabia, liberation of Iraq from a monstrous tyrant — are secondary compared to the historic mission for which the Almighty has chosen him.

To accomplish the mission, Bush has transformed the basis of American foreign policy. For the nearly half century of the Cold War, US foreign policy was founded on containment plus deterrence. Bush scrapped that. The new basis of US foreign policy is preventive war. As President Bush has said, “We must take the battle to the enemy... and confront the worst threats before they emerge.’’ The immediate reason that Bush opened Pandora’s box in the Middle East and invaded Iraq was his moral certitude that Saddam Hussein had weapons of mass destruction and that he was working in close partnership with Osama Bin Laden and Al-Qaeda. Those convictions turned out to be delusions. This denouement does great harm to Bush’s credibility and to that of the United States; it has got us into a ghastly mess in Iraq; and it has diverted attention, resources and military might from the war that should have commanded the Bush administration’s highest priority — the Afghan war against Al-Qaeda and international terrorism. Meanwhile Afghanistan is a mess too. Bush chose the wrong war in the wrong place at the wrong time.

The impact of the war on the election is hard to predict. In international crises, the American instinct is to rally round the flag and the president — for a while at least. Thus far, the protests against the war have not been extensive. But Fallujah has been compared to the Viet Cong’s Tet offensive in 1968, which set in motion a process that drove President Lyndon B Johnson from the White House.

The war’s impact depends on the success of the American occupation in stopping the disintegration of Iraq and achieving a measure of stability. It depends on the possible capture of Osama Bin Laden. It depends on the possible trial of Saddam Hussein. It depends on all sorts of unforeseeable variables. As Harold Wilson used to say, “In politics, a week is a very long time.’’ Six months is an eternity.

In a democracy, elected leaders must be held accountable. The war on Iraq was a matter of presidential choice, not of national necessity. The rekindled memory of Vietnam calls to mind a highly decorated young naval lieutenant returning from Vietnam named John Forbes Kerry, who put a poignant question to the Senate Foreign Relations Committee on April 22, 1971: “How do you ask a man to be the last man to die for a mistake?’’

— Arthur Schlesinger, Special Assistant to President Kennedy, 1961-4, is author of “The Bitter Heritage: Vietnam and American democracy, 1941-1966” .