Cold War vs. United States The Cold War ended in 1991 after the Soviet Union fell apart. Since then, Russia's economy paralyzed, and the United States is three trillion dollars in debt, and both counties were weakened by the Cold War because of military spending. To have world peace does not mean that United States should increase its military strength. The Realist theory would argue that military strength is important to maintain peace both domestically and internationally. Even though the United States as the only superpower remains in certain perspective, the U.S can not be the peace keeper for t