That assessment actually understates the terrible repercussions from the American defeat, whose ripples spread around the world. In the late 1970s, America’s enemies seized power in countries from Mozambique to Iran to Nicaragua. American hostages were seized aboard the SS Mayaguez (off Cambodia) and in Tehran. The Red Army invaded Afghanistan. It is impossible to prove the connection with the Vietnam War, but there is little doubt that the enfeeblement of a superpower encouraged our enemies to undertake acts of aggression that they might otherwise have shied away from.
Not only is it impossible to prove this case, but it is also possible to prove that Boot’s argument is wrong. Actually, Iran was lost because Carter dropped most meaningful support for the Shah and all but urged the Iranians to depose him. That was one of the early “victories” of a foreign policy of “values” and democracy promotion. The Shah was gone by February 1979. Afghanistan, which the Soviets invaded in December of that year, came at least partly as a result of the failure to respond effectively to the hostage crisis, but the Soviets had already been looking to counter what Moscow saw as American gains in the 1979 peace deal between Israel and Egypt and the beginnings of a pro-Western turn in Baghdad under you-know-who.
Mozambique’s communists came to power in the wake of independence from Portugal, and their internal policies provoked civil war. Their support for ZANU and the ANC provoked some of Mozambique’s neighbours to intervene against the government’s side. Naturally, the Soviets supported or at least sympathised with communist and pro-communist African movements, including the ANC, but the existence of these movements would not have been prevented by continued U.S. backing for South Vietnam. Obviously. The rise of communism in Mozambique (and Angola) had more than a little to do with resistance to Portugese colonialism and Portugal’s fairly intense efforts to prevent the independence of its African colonies. These were national or independence movements in which communists took a leading role; outside support did not create these movements.
The very same kind of limited thinking about the nature of Vietnamese communism that plagued policymakers in the ’60s and ’70s then seems to be plaguing latter-day Vietnam “hawks” when it comes to talking about African communist movements. The confusion is such that Mozambique can be cited as some sort of “proof” for the validity of the domino theory, when Mozambique was going to turn communist at that stage regardless of what happened in southeast Asia. Communists in wars of decolonisation were not all directed by the Supreme Soviet to advance Moscow’s foreign policy. Moscow might try to use these rebels as proxies after they had already started fighting, but communist control in Mozambique was primarily a result of their war for independence and not outside support. There is no meaningful connection to the aftermath of the Vietnam War.
Nicaragua’s story was rather like that of Iran. Carter was pulling the rug out from under Somoza (Carter’s foreign policy of “human rights” strikes again) and stopped all military support in 1978, which certainly did nothing to reduce Sandinista enthusiasm for overthrowing the government. The methods of Somoza’s dictatorship generated the resistance against the government, and the Sandinistas came eventually to dominate that resistance. You might make a very roundabout argument that Carter did to Somoza’s regime what had been done to South Vietnam’s, but the connection with Vietnam ends there. There is a certain irony that the policies that helped bring about these blows to U.S. power are the very ones–democracy promotion and championing of human rights–backed by the interventionists who are busily cheering on Mr. Bush’s blinkered revisionism. Naturally, if I were a partisan of the New Carter currently in the White House I would do all I could to deflect attention to the actual causes of U.S. setbacks during the late 1970s, since a discerning eye would be able to recognise an earlier version of Mr. Bush’s “freedom agenda” doing its pernicious work in undermining American interests. Indeed, each and every one of the examples cited has nothing to do with Vietnam and everything to do with a misguided idealistic foreign policy that the current administration seems intent on duplicating today.
Update: Separately, it seems relevant to the Drezner-Greenwald debate over the foreign policy establishment consensus to point out that Max Boot, a “paid-up” CFR man himself, has never had any difficulty endorsing the idea that the United States has been acting as an imperialist power.