Because it didn’t receive support from the senate. Also the U.S wanted to keep America out of European affairs.
If you were asked to write a summary of the 1968 presidential election, you would want to focus on "Hubert Humphrey, since he was the candidate who lost the election to Nixon.
The United States sent military forces to the Balkans during the 1990s in order to rescue people from atrocities committed against them--"crimes against humanity"--and to take the assertive action that NATO as a peace-keeping enterprise could not take to end the war.
