After Napoleon Bonaparte was defeated and exiled, the old monarchies of Europe acted quickly to reassert their old power. They crushed the democratic rebellions and restored dethroned monarchs to their thrones. Rumor had it that they wanted to destroy the new Latin America republics and restore the lands to colonial rule by Spain. Britain did not want this to happen because the monopoly-free ports of the new Latin American republics were profitable so the British minister at that time, George Canning, suggested that the United States and Great Britain jointly declare the Americas off limits to the European powers.
At that time, Russia was expanding its territory from Alaska down the west coast of the North American continent and the people in the United States was afraid that the Russians would cut the Americans off from its window to the Pacific Ocean. This, combined with the fact that the Americans were also profiting from the monopoly free ports of Latin America motivated the United States to make some kind of declaration. There was opposition to a joint declaration with Great Britain because they didn’t want to be morally held back from acquiring Spanish lands in the Americas. John Quincy Adams correctly saw that even if the United States did not join Britain the British would still protect the ports so he advocated a declaration by the United States without the British.
President Monroe announced to the world during his regular annual address to Congress that the era of colonization was over in the Americas and that the European powers were not to interfere in the new Latin American republics. Since Monroe said it, this “doctrine” was named after him. The Monroe Doctrine could be said to be a self-protection doctrine because the noncolonization part was mainly directed at the Russian who were expanding down the west coast and if they were stopped, the United States would be guaranteed access to the Pacific Ocean. The noninterference part was another way that the United States protected itself. If a European nation took control of any land in the Americas the United States would be in danger of invasions.
The Monroe Doctrine was an isolationist document because it prevented the interference of any European nation in the Americas. In the terms of the Monroe Doctrine, Monroe warned the European powers away from the western hemisphere and in return the United States won’t interfere with the war between the Greeks and the Turks in Europe. In short, the United States said that if Europe wouldn’t interfere with American affairs then the United States wouldn’t interfere with European affairs. By rejecting the British hand in partnership, the United States also followed the policy of isolationism because they did not accept European help even though their military was no match for European armed forces.