The correct answer is the following.
President Ronald Reagan asked for a formal request to invade Grenada even though he had already decided to invade. President Reagan asked for a formal request to invade Grenada because he wanted the international approval and support for the invasion. It was much better for him to have the approval of many countries of the world to invade because he did not want to present a scenario of an authoritative invasion.
The United States invaded Grenade on October 25, 1983. Reagan considered that the Marxist regime in Grenada was a threat to the United States security. The invasion lasted one week. The Marines controlled the situation and overthrew the Communist government.