Politically, President Bush has reached the point all gamblers fear: being so far down that higher stakes start to look worth the risk. Public support for his handling of the war in Iraq is already abysmal, with 70% against him and only 25% still in his camp. So perhaps he felt he had very little to lose when Wednesday, in a speech to the Veterans of Foreign Wars in Kansas City, Mo., he effectively doubled down, arguing not only that America needs to stay in Iraq until a stable democracy can take root, but also implying we should have done the same in Vietnam a generation ago....

In the end, it is the familiarity — critics would say the lack of credibility — of those themes that provide the answer to Bush's risky invocation of Vietnam. He has so often emphasized the disastrous ramifications of failure and the potential glories of victory, they no longer hold the same currency with a war-tired public. So, given how low support for the war is, why not add the specter of Vietnam to the costs of defeat? And why not suggest that victory in Iraq could help expunge the indignity of America's loss in Vietnam? Petraeus and Crocker will say what they will regardless of Bush's assertions, so raising the rhetorical stakes in the hopes of bolstering political support ahead of their report is the only card Bush has left to play.