The purpose of the Monroe Doctrine was to stop European colonization in the Western Hemisphere. James Monroe established this doctrine in a speech to Congress in 1823. At the time of this address, Monroe's primary concern was the welfare of Latin American countries.
In the address, Monroe stated the United States would not involve itself in European affairs. He promised not to interfere with any existing European colonies in the Western Hemisphere, but refused to allow any other nation to begin a new colony there. Monroe further stated that the United States would see any further attempts to begin new colonies as an act of aggression.
The United States did not invoke the doctrine for several decades, until it seized Texas from Mexico in 1842. Theodore Roosevelt used the power of the Monroe Doctrine in helping Cuba to gain its freedom from Spain. John F. Kennedy referred to the Monroe Doctrine during the Cold War and the Cuban Missile Crisis. Ronald Reagan referred to this document in his first term and used it as justification for the Falklands War of 1982, laying the groundwork for George Bush's invasion of Panama without invoking the Monroe Doctrine. In 2013, Secretary of State John Kerry said the Monroe Doctrine is dead. He called for keeping the initial message of the doctrine without the policies that have framed it since Monroe's death.