Iraq and Vietnam
I agree that teaching students both about how policymakers used historical analogies and how students themselves can employ historical analogies comes with the territory when teaching courses in US foreign relations. But the Young piece (quite beyond its unusual and unconvincing sourcing) scarcely serves as a model in this effort.
It would be hard to argue that the Bush administration didn't politicize intelligence in the run-up to the Iraq war or badly botch the postwar planning by basing policy on a best-case scenario without any fallback plans. Yet the critique of the academic anti-war movement has been, if anything, more shrill, and the Vietnam analogy of which Young seems quite fond strikes me as misguided.
The differences between Iraq and Vietnam are considerable, making comparisons tricky at best and misleading at worst. A few off the top of my head:
(1) Vietnam was a creeping commitment; in the Iraq war, the number of US troops has been basically static. (2) The US army in Vietnam was mostly conscript; the US army in Iraq is technically all volunteer and de facto mostly volunteer. (3) In Vietnam, the US ally never was a legitimate government in a conflict that at least began as a civil war, while the other side did have such a regime; in Iraq, at least after the elections, the US ally does represent a legitimate government, while the other side has no such regime. (4) The war in Iraq was much more controversial--internationally, in Congress, and among the American public--than was the conflict in Vietnam at a comparable stage. (5) Constitutional processes were followed in the war in Iraq, whereas in Vietnam, no President ever submitted to Congress a resolution intended to authorize the war. (6) From a realpolitik standpoint, a precipitate US withdrawal from Vietnam (say, the Aiken strategy) would have caused no harm and almost certainly would have benefitted the United States; that certainly cannot be said with the Iraq scenario. (7) In Vietnam, the enemy was receiving support from two superpowers; the Iraqi enemy has no such international state-based backing. (8) The international and domestic media is far more skeptical about US foreign policy now than at a comparable stage in the Vietnam War, when few dissenting voices existed.
This is not to say anything one way or the other about the merits of the war in Iraq. But we ill serve our students by making historical comparisons that might serve a political agenda but don't hold up well under scrutiny.