Vietnam syndrome

The Vietnam syndrome infected American political leaders from the mid-1970s until the late 1990s.

After the end of the Vietnam War, American presidents were loathe to send U.S. troops into combat situations for fear that, as had happened in Vietnam, a prolonged engagement (or a "quagmire," to use the common parlance) would lead to a loss of support for the administration.

Case studies
Two examples of the syndrome in action are the sudden withdrawal of U.S. Marines from a peacekeeping mission in Lebanon following the suicide bombing of their barracks in 1983, and the removal of American forces from Somalia after the infamous "Black Hawk Down" incident a decade later.

With the nation emboldened by its successes in the first Gulf War, the Kosovo War might be seen as the first sign that America had recovered from Vietnam syndrome; the broad support that the political establishment gave to the invasions of Afghanistan and Iraq and the lack of dedicated, enduring mass protests against those wars suggest the syndrome is a thing of the past.