In a new CNN/Opinion Research Corporation poll, 52 percent of people questioned say that the 8-year-old Afghanistan conflict has turned into another Vietnam War. Is there anything to be learned from the comparison? (Watch the man behind the 1968 "Pentagon Papers" leak on "Vietnamistan".)

It’s pointless to compare the wars: The American tendency to turn every conversation about Afghanistan into a rehash of debates about Vietnam "is really quite perverse," says Matthew Yglesias at Think Progress. "And not just because the countries are different but because the situations are so different." In Afghanistan, we’re not facing the threat of a communist victory: "Vietnam wasn’t an abstract exercise in U.S. military prowess. It was part of the Cold War."
Reading Material

The levels of anguish are certainly parallel: In interviews before their deaths, say Bob Woodward and Gordon M. Goldstein in The Washington Post, two of President Lyndon Johnson’s key Vietnam advisors spoke frankly about the dysfunctional decision process involved in that war. "I felt that I owed [Johnson] my best judgment ...," said then–Secretary of Defense Robert McNamara. "The question was how to present it effectively to a man who didn’t want to listen."
The Anguish of Decision

The key similarities can’t be overlooked: As in Vietnam, say Stephen J. Solarz and Michael O’Hanlon in The Washington Times, "we cannot succeed [in Afghanistan] without a viable domestic partner. Right now Mr. Karzai's government is not measuring up, and so we must use every tool at our disposal to push, prod, and cajole him to a higher standard of effectiveness."
An Intermediate Option