In his trademark V-neck sweater, with the day’s newspaper tucked under his arm, Mort Sahl has satirized — and entertained — presidents from Eisenhower to Obama. He revolutionized the world of stand-up comedy with a fresh combination of political awareness, fearless criticism of the government, and a willingness to draw on personal experience. It is limiting to call Sahl a comedian or a satirist, but he was the first of a kind to have “attitude,” before attitude became a substitute for wit. His refusal to play favorites with the political community made him the center of intense controversy, and his involvement with John F. Kennedy nearly cost him his career. But through it all, Mort Sahl has remained an unflinching critic of American politics, and he has never backed away from his beliefs.