"During 1965 and 1966," wrote Dale Andrade, a historian at the U.S. Army Center of Military History, "the Communists fought the Americans toe to toe, making little effort to act like guerillas." Indeed, despite pronounced disadvantages in firepower and mobility, the Communist Vietnamese endeavored to crush South Vietnam and expel the American military with a strategy predicated on "big unit" war. Orchestrated by a militant clique in Hanoi, the "big...