If you think things aren't going well in Iraq now, just wait until the start of election season next year.
Yes, this is known as 'fighting the last war' - it's one of the most common but most foolish of errors in strategic thinking. Vietnam provides no more insight than any of the world's 1,000 previous wars do, and the worst thing is to imagine Iraq will follow the same pattern. It wont.
Just because your average Democratic presidential candidate is that stupid and foolish, doesnt mean the rest of us should be.
There are dozens of better analogies of our current situation: I think of reconstruction South circa 1868 as one 'template', with the baathists as the KKK; Japan and germany 1945 is another; yet another is the Philipines 1901; yet another is Lebanon in 1980s; our wars against the plains indians; yet another is Turkey in the 1920s; El Salvador 1980s; etc etc Of course my favorite would be Alexander the Great, who won his great battle of Arbala on the plains of Euphrates in today's Iraq, and pacified successfully the Persian empire by allowing intermarriage of troops and treating the losing armies and peoples respectfully. It changed the course of civilization, creating a "greek hegemony" that evolved (was absorbed by) the Roman empire, that became byzantium (constantinople), that taught the Arab empire based in Baghdad all they know, which became the greatest civilization of the 9th century, and through Islam shaped our modern world... All because Alexander the Great WON THE PEACE. Ah, if we could pull that trick off!
Vietnam is a poor analogy, and is only considered because most people including our politicians are historical illiterates.