Final answer:
Richard Nixon, as the US president, ended military involvement in the Vietnam War in 1973 by signing the Paris Peace Accords.
Step-by-step explanation:
The US president who finally brought an end to military involvement in the Vietnam War in 1973 was Richard Nixon. He signed the Paris Peace Accords, which marked the official end of U.S. force commitment to the war. However, the peace was short-lived, as the North Vietnamese troops quickly overwhelmed the South Vietnamese forces and the country was eventually unified under a communist government in 1975.