Rick Perlstein reviews the two big revisionist histories of the Vietnam war that have come out lately, both of which conservatives have used to argue that the U.S. military was actually winning the conflict—before, of course, being betrayed by those pesky liberals in Congress. Shockingly, both books are pretty shoddy (curiously, one of them, Triumph Forsaken, goes about uncritically accepting Communist missives in order to make its case).