Yesterday, we mentioned the nostalgia for the past emanating from the left and the press. Nowhere is that more apparent (well, other than at a Creedence Clearwater Revisted concert) than the endless references to Vietnam. In an essay on the 30th anniversary of the fall of Saigon, Jonah Goldberg observes:

Since the beginning of the second Iraq war, comparisons, insinuations, allusions to Vietnam have been a near-daily occurrence. Literally thousands upon thousands of articles and editorials make the analogy as though it were actually a novel insight. You get the sense that Earth could be invaded by Klingons and some editorialist would hear "echoes of Vietnam" amid their disruptor blasts.

One is tempted to simply chalk this up to the geezerification of liberal baby boomers who can't shake their nostalgia for the glory days of speaking truth to power. But many of today's younger generation have been Vietnamized as well. This isn't as odd as it might sound. World War I seemed like ancient history before the ink on the armistice was dry. World War II, meanwhile, continues to dominate our imaginations, on the right and left, six decades after it ended. As any historian will tell you, public understanding of WWII has become far more literary than literal. So it is with Vietnam.

There's an enduring myth that Vietnam was a singular evil undone by America's idealistic youth, holding hands and singing songs in one voice for peace. This reflects the ego of baby-boomer liberals more than the facts. Not only did large numbers of young people support the war, but in the annals of unpopular wars, it wasn't that special. In 1968, Sol Tax of the University of Chicago cataloged anti-war activity from the Revolutionary War until the beginning of peace negotiations and found that Vietnam ranked as either the fourth or seventh least-popular war in American history.

Regardless, Vietnam is part of our cultural DNA now, and it will probably never be fully erased anymore than the Civil War or WWII will be. Right or wrong, silly or legitimate, that's the reality. And that's fine. If people want to argue about the Tet Offensive forever, so be it. But it is history.

But it's not particularly useful history. Ask military experts about the similarities between Vietnam and Iraq (or Afghanistan), and their eyes roll. Vietnam was a state-to-state war and had vastly more support from its Communist benefactors than Iraqi "insurgents" could ever receive from Syria and Iran. Indeed, in Vietnam, the insurgency phase of the war was largely over by 1965.

The Spanish-American War, for instance, would probably be a far more fruitful point of comparison for critics of the Bush administration, but that would require they read up on it first.