The U.S got involved because on December 7th, 1941 the Japanese launched a surprise attack on the U.S bombing pearl harbor in Hawaii. Soon afterwards the U.S declared war on japan and joined the war officially in 1941
The Vietnam war
Communisms was beginning to get out of hand and got to china president Truman had wanted to 'contain' communisms so the U.S got involved from the year 1950 to 1953
First gulf war
After the bay of pigs invasion, Russia started sending Castro nuclear weapons to be fired at the USA, in 1962 American spy planes found that Cubans were secretly building bases for nuclear missiles. this was the closest the world has ever gotten to a nuclear war.
Iran hostage crisis
The cold war spread to southeast Asia. aka Vietnam, north Vietnam was placed under communist control, President Kennedy sent advisors to help south vitaminizes government. in 1964 there was a claim that there was an attack and thus they got permission to sent troops to Vietnam.
Sandam Hussein invaded neighboring country Kuwait. President bush decided to act and built an coalition of international forces who apposed of his actions. U.S forces were sent to Saudi Arabia to protect them then moved to Kuwait and when Iraq troops got there they were defeated.
In 1979, The Iranian government let a angry mob take the staff of the U.S embassy captive in their capital city of Tehran. The hostages were kept there for almost a year and were not officially freed until 1981