People who believed that the US should take care of its own problems and stay out of foreign disagreements.

People who believed that the U. S. should take care of its own problems and stay out of foreign disagreement is a isolationist. Isolationism refers to America's longstanding reluctance, it is a is a person who believes in keeping to one's own affairs rather than becoming involved in the affairs of others. The isolationist perspective dates to colonial days.