Members of Congress surround President Jimmy Carter at the State of the Union address on Jan. 23, 1980. Fifty Americans were being held hostage in Iran and the Soviets were occupying Afghanistan. Carter used the address to lay out the Carter Doctrine: “An attempt by any outside force to gain control of the Persian Gulf region will be regarded as an assault on the vital interests of the United States of America, and such an assault will be repelled by any means necessary, including military force.”