South Vietnam was abandoned to the communists under the Republican administration of Gerald Ford. In 2006 communist Vietnam signed a special trade agreement with the US reducing tariffs to 15% or less for most Vietnamese goods brought into the US and eliminating completely all textile and apparel quotas. The legislation was signed by Republican President George W. Bush. The Vietnamese communists we sacrificed over 50,000 lives and billions of dollars to defeat are now major trading partners. It is ironic the Republican Mr. Bush decided to sacrifice American jobs to build up the economy of still communist Vietnam. Seems like something Mr. McGovern would applaud.
A post-Watergate Congress refused any further military assistance to the Republic of Vietnam in or about March 1975. Gerry Ford couldn't do squat.