The Carter Doctrine was President Carter’s declaration that the United States would not tolerate Soviet attempts to gain control of the Persian Gulf region. Carter proclaimed in his January 1980 State of the Union address: “Let our position be absolutely clear: 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.”