The difficulty with maintaining neutrality for America during WW I was that America was doing business with England, and Germany was attacking the American shipping.
They Passed the Neutrality Act.
Germany occupied many nations during WWII, including France, Denmark, Luxembourg, Belgium, Netherlands, Poland and Norway.
The two neutral nations that shared a large peninsula north of Germany and Denmark are Norway and Sweden. Located on the Scandinavian Peninsula, both countries maintained a stance of neutrality during World War I and World War II. Their geographic proximity and historical ties have contributed to a longstanding relationship, characterized by cooperation and cultural exchange.
Switzerland, and Sweden maintained neutrality. Spain was in the grip of Franco, and kept quiet.
U.S., Germany, Japan, France, and U.K.
During the Cold War, the nation of Germany was partitioned into two nations, which were West Germany, which was allied with NATO, and East Germany, which was a member of the Warsaw Pact.
France and Britain violated American neutrality during conflicts like the Napoleonic Wars by interfering with American trade and imposing restrictions on U.S. shipping. Britain implemented a blockade of French ports, seizing American ships and cargo, while France retaliated by capturing American vessels trading with Britain. These actions strained U.S. relations with both nations, leading to tensions that ultimately contributed to the War of 1812.
United States, Germany, Japan, France, and United Kingdom
durin the cold war the three nations that got divided were Korea,Vietnam and,Germany
Germany and Britain
Germany, Poland, and Belgium.