Why did the United States help Kuwait in the Persian Gulf War in 1991?

Iraqi president Saddam Hussein ordered the invasion and occupation of neighboring Kuwait in early august 1990. Alarmed by these actions fellow Arab powers such as Saudi Arabia and Egypt called on the United States and other wester nations to intervene. Hussein defied United Nations security council demands to withdraw from Kuwait by mid January 1991 and the Persian gulf war began with massive US led air offensive known as operation dessert storm.