Former Secretary of State Alexander Haig, a four-star general who served as a top adviser to three presidents and had presidential ambitions of his own, died Saturday of complications from an infection, his family said. He was 85. Haig's long and decorated military career launched the Washington career for which he is better known, including top posts in the Nixon, Ford and Reagan administrations. He never lived down his televised response to the 1981 assassination attempt on President Ronald Reagan. Hours after the shooting, then Secretary of State Haig went before the cameras intending, he said later, to reassure Americans that the White House was functioning. “As of now, I am in control here in the White House, pending the return of the vice president,” Haig said. Haig died at Johns Hopkins Hospital in Baltimore, where he was surrounded by his family, according to two of his children, Alexander and Barbara. A hospital spokesman, Gary Stephenson, said Haig died at about 1:30 A.M.