History repeats itself, but rarely exactly. Examples of both cowardice and courage have lessons to teach, and so do comparisons with the past. The oft-drawn analogy between abrupt withdrawal from Iraq and Neville Chamberlain's appeasement of Hitler in 1938 is inexact, but irresistible. Chamberlain, like some of the loudest voices crying now for taking the last plane out of Baghdad, was regarded by his colleagues and the newspapers as "a hero for peace."

Though many Englishmen knew better, few politicians were brave enough to speak up when Chamberlain returned from meeting Hitler in Munich in 1938, proclaiming "peace in our time." Sentiment prevailed, emotion ruled. Gratification of the moment trumped appeals to the longer view. A cool assessment of harsh and unforgiving reality gave way to a rose-colored view of an imagined world at peace and play.

Those who knew in their hearts that Chamberlain had betrayed Czechoslovakia nevertheless felt relief, reassuring themselves that, after all, appeasement is always better than war. Francis Williams, the editor of the Daily Herald, a Labor newspaper, was typical. He might be a peace blogger today. Refusing to consider warnings that Hitler would exploit Chamberlain's retreat to make matters worse, he focused on images of children, including his own, playing in peaceful streets and country lanes, doing handstands or riding their bicycles: "Such things -- and a hundred others -- came between intellect and will," he said, "and cried out that it was worth doing anything to avoid war."

In her book "Troublesome Young Men: The Rebels Who Brought Churchill to Power and Helped Save England," Lynne Olson captures the spirit of the time and shows how difficult it was to argue against the prevailing anti-war atmosphere. Who, after all, wants war? Who doesn't prefer peace to turmoil? Nevertheless, when Hitler marched into Poland, England declared war -- and did nothing else. Mocking Teddy Roosevelt's famous maxim, Chamberlain spoke loudly and carried a small stick.

It took a few troublesome young Tories to defy Chamberlain's policy of defeat, putting their careers at risk (and most of them paid a price) to oust Chamberlain and bring in Winston Churchill. What's clear only in retrospect is how hard it is to invoke common sense against the peace mob. If we're lucky, there will be a troublesome young man to make trouble. Duff Cooper was the first lord of the admiralty in 1938. He liked his job and wanted to keep it, but resigned in protest. "It was 'peace with honor' that I couldn't stomach," he said. "If [Chamberlain] had come back from Munich saying 'peace with terrible, unmitigated, unparalleled dishonor,' perhaps I would have stayed. But peace with honor!"

Words like these reverberate now in Washington. Even before we get the eagerly awaited September progress report from Gen. David Petraeus, the U.S. commander in Iraq, the peace-at-any-price mob can't wait to declare peace. Honor has nothing to do with it. The peace mob already knows all they want to know.

Terrorism is not fascism, but the terrorists have the familiar lust for blood. Osama bin Laden is not Adolf Hitler, but like Hitler he recognized vulnerability in the West when acts of terror against the American embassies in Africa, the USS Cole and the first bombing of the World Trade Center went unanswered. The plotters of al Qaeda similarly recognize faint hearts in the West. Friends as well as enemies are measuring how dependable an ally America and Britain really are. Evil men in Afghanistan and Iraq can't invade the West, but the first line of defense runs through those miserable places.

George W. Bush is no Winston Churchill, but he can learn from him. Churchill offered his people a deep understanding of why war was both necessary and inevitable, and asked for their help. He got it. Three days after he replaced Chamberlain, he replied to his skeptics: "What is our aim? I can answer in one word: victory." Gordon Brown, the new British prime minister, is no Churchill, either. He describes the war in the dullest of dull language: "In Iraq we have duties to discharge and responsibilities to keep." No ringing call to arms there.

The Iraq war is unpopular, but losing it would be disastrous. Rudolph Giuliani got it right in the Sunday morning Republican debate in Iowa: "The reality is that you do not achieve peace through weakness and appeasement. . . . We should seek a victory in Iraq and in Baghdad, and we should define the victory." Looking reality in the eye is the work of troublesome young men -- and women. Is there now one among us?