The U.S. are the #1 aggressor nation of our times.
I wish I could refute that, but that statement may be true since the Cold War ended. Prior to that I think an argument could be made that those countries behind the Iron Curtain were at least as aggressive as we were, and prior to WWII, the European colonial powers were much more aggressive than the U.S..

Like most nations we have parts of our history that we're not proud of, but what other nation has sacrificed so much (men and material) in pursuit of humanitarian efforts, such as our intervention in Haiti, Somalia, Bosnia, Kosovo, Liberia, and our diplomatic efforts elsewhere such as Sudan, Burma, China, and several others where we pushed for human rights? Name one if can.

A lot of ugly things happened during the Cold War that in hindsight probably weren't really in our interests, but the intentions at least were based on what perceived as a greater good (ends justify the means). The mass murders that took place in the USSR and China under Stalin and Mao were not myths, the communist system needed to be defeated for the good of all mankind.