A spokesperson for the Department of Defense (DOD) said that most U.S. troops will arrive in Kabul by the end of the weekend, adding that some troops have already arrived. “We have noted with great concern the speed with which they have been moving,” Pentagon spokesman John Kirby told reporters, referring to the Taliban having taken over swaths of the country in recent days. When asked about the fall of Saigon in 1975, or when Vietnamese communist forces took over the capital during the Vietnam War, Kirby pushed back against comparing that situation to the one that’s unfolding now in Afghanistan. The United States, at the time, was forced to evacuate thousands of American civilians and some Vietnamese via helicopters, leaving a number of enduring images. “We’re not focused on the history of the Vietnam War,” Kirby said. But Kirby said that he cannot predict whether the Afghan army would …