In the immediate aftermath of the terrorist attacks of September 11, analysts were divided about its meaning. For some, including President Bush, it represented "the first war of the 21st Century." For others, including George Will, it was a continuation of the last war of the last century, an extension by other means of the Persian Gulf War against Iraq. What recent anti-war demonstrations have shown, however, is that our current crisis can be also be viewed as the last battle of the Vietnam War.

Those demonstrations, and much intellectual commentary surrounding them, show a familiar scene: the usual suspects wielding the usual slogans and using idealistic (not to mention historically ignorant) youth as their fodder. However, over the past thirty-five years, their argument has been gradually stripped to its essence, until now little remains but its hard core, the twin towers of anti-Americanism and pure naiveté.

It is hard to believe today, but the original composite anti-Vietnam war argument was relatively complex and respectable. It went something like this: we do not support our country because it is fighting a war far away for unclear purposes on behalf of a corrupt, repressive regime against a popular insurgency. If America were fighting for freedom, against clear international aggression, or to defend our own homes, of course we would support it.

The argument was terribly flawed; as it turns out, in Vietnam we were fighting for freedom (remember the "boat people" and the killing fields of Cambodia?) and against external aggression (there is no doubt that the war was driven by North Vietnamese regional imperialism). Subsequent events have dismantled it piece by piece.

When the United States sent troops to Grenada in 1983, they liberated the island from a bloody dictatorship and were welcomed with open arms by most Grenadians. America was clearly on the side of freedom. Yet the slogans and the protests continued, as if Grenada were Vietnam.

When the United States sent troops to free Kuwait in 1991, America was not fighting an insurgency but an Iraqi army sent across an international border to conquer and pillage another country. America was clearly fighting as a response to an act of naked aggression. Yet the slogans and the protests continued, as if Kuwait were Vietnam.

When the United States was attacked on the morning of September 11, 2001, without warning and without provocation, the target was our own people on our own soil. America, not some other land far away, was the victim. Yet, even before we responded—as the remains of Americans were even yet being dug out of the rubble—the slogans and the protests continued, as if the World Trade Center was Vietnam. Osama bin Laden has joined the Viet Cong in the Manhattan Delta, and our protestors are unfazed. For them, nothing has changed. No one can take seriously any longer the anti-war argument of 1968.

Anti-war forces are consequently forced to fall back on a battery of secondary propositions held together by little more than their common ludicrousness. Would a military response by the United States unleash a "cycle of violence?" For fifteen years, there has been no "cycle of violence," only a linear progression of violence as our enemies attacked us repeatedly with little or no effective response. It is true enough that retaliation will be followed by more terror. What the anti-war forces cannot admit is that failure to retaliate will also be followed by more terror. The only question is whether the United States will defend itself.

Is this really a "criminal" matter to be handled exclusively by the World Court or U.S. judicial authorities? We have already tried that approach and it failed miserably. After the first bombing of the World Trade Center, we convicted and imprisoned a small handful of bit players who were involved. They were simply replaced, and the mission was resumed. September 11 was not grand theft auto on a large scale.

Did U.S. policy incite the terrorists to this mayhem? As columnist Charles Krauthammer asked, which U.S. policy would that be? The U.S. policy that saved the Muslim Somalians from starvation; the policy that helped rescue the Muslim Afghans, Kuwaitis, Bosnians, and Kosovars from brutal occupation by hostile armies; or the policy that pressured Israel into the land-for-peace deal with Yassir Arafat? There is no U.S. policy in the Middle East short of throwing Israel overboard and completely abandoning the region to the forces of militant Islamism that would satisfy Osama bin Laden’s demands.

Are we turning "a tragedy into a war," as the protestors like to say? A tragedy is when a two-year-old drowns in a swimming pool or a tornado overturns a trailer park. September 11 was not a "tragedy." It was a deliberate, calculated act of war by an organized force whose leader openly declared war on America three years ago and whose Islamo-fascist ideology is committed to bringing America to its knees. Would the protestors think the U.S. military response was acceptable as long as we call it a tragedy?

No, the anti-war movement long ago turned its talents from tragedy to farce. All of the conditions it established for its support of American self-defense thirty-five years ago have been met, and yet it opposes American self-defense. In the end, the perpetual protestors are one part unconquerable naiveté, one part knee-jerk insistence on blaming America and embracing its enemies no matter how foul, and one hundred percent nostalgic narcissism. Now that the illusions are gone, they have nothing left but "Give Peace a Chance" and "Ho, Ho, Ho Chi Minh, the NLF is gonna win." Maybe that is all they ever really had.

Andrew E. Busch is an Adjunct Fellow of the John M. Ashbrook Center for Public Affairs and an Associate Professor of Political Science at the University of Denver, where he specializes in American government and politics. Dr. Busch is the author of Ronald Reagan and the Politics of Freedom. He is also the co-author of The Perfect Tie: The True Story of the 2000 Presidential Election.