One of the most important duties of the American forces was to support diplomatic efforts to achieve a political settlement and provide troops for the IAPF. After the OAS peace commission arrived and American troops cleared the corridor joining the marine and paratrooper positions, the duties of the troops consisted of maintaining order in Santo Domingo, ensuring that rebel forces were contained in their stronghold in downtown Santo Domingo, and restraining the loyalist forces from attacking the rebel stronghold.
During the first few days of the crisis, when American officials thought the rebel faction might win, U.S. policy favored the junta and American military forces supplied the loyalists with communications equipment and other support. After the U.S. military buildup American policy shifted toward a more neutral stance and Washington used military force to restrain the junta from attacking the rebel stronghold. Finally, U.S. policy shifted toward backing a Dominican provisional government and, as part of the peace force, U.S. units participated in actions in support of the new government. 1
President Johnson sent Ambassador Martin to the Dominican Republic to obtain information, to arrange a cease-fire, to contact the rebels, and to investigate the possibilities of a political settlement. In order to accomplish the last, Martin investigated General Imbert as a possible candidate to form a new government. American officials wanted to broaden the base of the rightist San Isidro government, for it seemed Caamaño and the rebels would never reach an understanding with Wessin y Wessin and the San Isidro generals. Washington did not want to associate the United States too closely with the Wessin y Wessin-backed Benoit junta, which represented a symbol of oppression to the Dominican people. Martin decided to back Imbert, for a rapprochement between Caamaño and Imbert appeared possible.