Still, though, if you're going to run on a single issue you've got to be brighter and more insightful than this essay suggests he his (or, you've got to not show the rest of the world the product of your manic phase). Slate.com has an article up picking apart his essay, but they may have had to edit for length. I would like to humbly add some comments about this section:
America must remember one of the lessons of the Vietnam War. Then, as now, we fought a war with the wrong strategy for several years. And then, as now, we corrected course and began to show real progress. Many historians today believe that by about 1972 we and our South Vietnamese partners had succeeded in defeating the Vietcong insurgency and in setting South Vietnam on a path to political self-sufficiency. But America then withdrew its support, allowing the communist North to conquer the South. The consequences were dire, and not only in Vietnam: numerous deaths in places such as the killing fields of Cambodia, a newly energized and expansionist Soviet Union, and a weaker America. The consequences of abandoning Iraq would be worse.
Our goal is to see in Iraq and Afghanistan the emergence of stable governments and societies that can act as our allies against the terrorists and not as breeding grounds for expanded terrorist activities. Succeeding in Iraq and Afghanistan is necessary but not sufficient.
I'm not a historian by any means, but I can't imagine who the "many historians" he refers to are. I've heard nobody claim the South Vietnam was ever anywhere near a "path to self-sufficiency" before the United States withdrew its troops. Indeed, one need not be very smart or ambitious to find, after a little time in the LBJ Presidential Archives, that nobody in the Kennedy or Johnson administrations ever regarded the Vietnam War as winnable, nor the southern country's government as anything like stable. The VietCong were very much in control of both the north and the south by the time the US landed it's first combat troops. The US then spent a huge amount of time, money and lives staving off the inevitable in hope that there might be an off-chance we could make the south end up as anything but communist.
That last point is crucial. The Johnson Administration, at least, had no illusions that they could make South Vietnam stable and friendly to US interests. All they sought was to keep it from the communists. Guiliani seems to think that a crucial first step towards winning the Global War on Terror is to create the sort of countries out of Iraq and Afghanistan that everyone knew was already off the table when Vietnam started. That's like predicating the solution to an insoluble problem on the successful completion of the impossible.*
*Lest I feel or be seen as a plagiarizer, I will point out that the more obsessive fans of Michael Chabon's The Amazing Adventures of Kavalier and Clay might recognize that sentence.