As it was the height of the Cold War, the U.S was sending troops every which way, as many Capitalist Countries did. Most Notably in this time woult have been:
Troops for open combat in Korea, as the Korean War was in full swing (1950-1953) between North Korea (Pro communist) and South Korea (Pro-Western)
West Germany, as it was vital to Western Defense in case of a Soviet Assault.
South Vietnam, U.S Military Advisers, though i believe open combat between Americans and Pro-communist forces started in 1954-55ish, but nothing heavy.
Netherlands
Netherlands
Any country with an army or militia will send there troops into a conflict or war.
Kuwait
1.5 trillion
If they're necessary and requested by the host country.
The United States would send troops to a democratic developing country if it was threatened by a nuclear power.
Answers doesn't have the answers to everything never use it again or use it as your last resource for anything :)
japan
The executive branch, covered in Article 2 of the Constitution.
Cambodia
Hitler did not send troops to the future.