"Doves for McCain"

Matt Welch, an editor for the libertarian-leaning Reason magazine, has an interesting opinion article for the LA Times on how antiwar moderates are breaking for Sen. John McCain. The irony, of course, is that McCain has a more interventionist foreign policy than President Bush does. (And that's saying something!)

That trend raises a question to my mind: why hasn't there been a strong, mainstream antiwar movement in the United States? Much of the Democrats' successes in the 2006 congressional election were due to their opposition to the President's handling of the war (and to the war itself). Have they delivered? Why not, given the popular support they had? And why have conservatives, who once articulated a foreign policy of prudence that eschewed "nation-building" and led to caution concerning American intervention overseas (see the following articles on the late Sen. Robert Taft here and here), tended to try to silence their lone antiwar candidate?

Any thoughts out there about this?