Our liberal friends are in a fury of indignation once again! This cannot be good for their health. A couple weeks back the source of their anger was the Administration’s repeated references to the 1930s, which is apparently a very sore spot with them. Now they are again indignados, owing to our suave president’s mention of Iraq during a speech commemorating the fifth anniversary of the 9/11 attacks. Presumably, we could prevent these unseemly eruptions if the Republicans would clear their speeches with Dr. Howard Dean. Of course, if the volcanic doctor had to vet all of them he might suffer some sort of seizure how would anyone know? He seems to be extreme much of the time.

The war in Iraq has obviously gotten to the Democrats. A few decades back the war in Vietnam got to them too, but in the war’s early years it was a minority of Democrats who opposed the war. Only after the hellish Richard Nixon became president did defeatism spread more widely among what had once been called Cold War liberals. Yet at least in the Vietnam War the anti-war liberals could point to a plausible exit strategy, to wit, negotiations.

The North Vietnamese Communists had the sense to present themselves as ready to negotiate and with a dulcet offer to the Americans, “peace and freedom and democracy in a united Vietnam” — ha, ha, ha. Today there is no one plausible to negotiate with in Iraq or in Afghanistan, and there is nothing even meretriciously attractive to negotiate about — though Nancy Pelosi adorned in a burkha has its appeal, as does fat Senator Kennedy denying his firewater.

I have to admit that when we invaded Iraq, and so many Democrats were hailing the invasion as a blow for freedom, I, in my youthful idealism, thought this would be one war they would not abscond from. Saddam was a contemporary Hitler. He had used weapons of mass destruction on his own people and for the purposes of genocide. He defied United Nations resolutions to search for them and was usually ambiguous as to whether he had them. He labored to dupe leaders in the Arab world and his generals into thinking he had them. (See “Saddam’s Delusions” in the May/June 2006 Foreign Affairs.)

He gave rewards to suicide bombers, and harbored terrorists on his soil, for instance the late Abu Nidal, the mastermind of terrorist attacks in over 20 countries, including the hijacking of the Achille Lauro. How closely Saddam was linked to the Islamofascists is a matter for historians to thrash out, but he certainly abetted their mischief. For years prior to the arrival of our troops at his gaudy palaces both he and the terrorists were enemies of our country and our Western values.

On that both Presidents Clinton and Bush seemed to agree until the 2004 presidential elections drew nigh. Then what had been a small anti-war movement composed mainly of cranks such as Noam Chomsky began to gather up liberal Democrats until it now comprises much of the Democratic leadership. How do we explain it?

In a thoughtful and timely Wall Street Journal column Bret Stephens offers this, “Here’s a puzzle: Why is it so frequently the case that the people who have the most at stake in the battle against Islamic extremism and the most to lose when Islamism gains — namely liberals — are typically the most reluctant to fight?” They have also been the first to bug out of Iraq, which one would think does not put liberals in a good light.

Mr. Stephens advances several reasons, none of which diminishes the irony of his point. He offers the liberals’ “instinct for pacifism,” their moral relativism, their weakness for appeasement and their confusion of Islamism with opposition to materialism and to the corporate world.

But I have an additional explanation. The liberals are uncomfortable being on the side of bourgeois conventionality. Some see this as anti-Americanism. Actually it is something more amusing.

It stems from the liberals’ only unwavering political value, the political value that now stands alone at the heart of liberalism. That value is a misdemeanor in the criminal codes of most civilized countries. It is disturbance of the peace. Drop a liberal into a community where conventions have been established and where civility reigns and our liberal friend will find some triviality to protest. Our liberal friends are congenitally alienated.

Thus for a few months, perhaps even a year, they opposed the Islamofascists and favored bringing down Saddam. Then they noticed whose side they were on. Yuk, and so they oppose this war, while offering no alternative — unless it be Ms. Pelosi in a burkha and rotund Teddy on the wagon.

Mr. Tyrrell is founder and editor in chief of the American Spectator, a contributing editor of The New York Sun, and an adjunct fellow at the Hudson Institute.