Sure it is. But what about cause and effect? Communism, Socialism, and Fascism all require an enemy to function efficiently. When we surrender liberty for comfort to those systems that are evil, we will be required by such systems to fight to perpetuate their evil.
Bring them to justice? There is no justice that will bring a single person back. There is no evil that is ever good. Punish the perpetraitors, fortify, rebuild, and above all do not persist in creating reasons or opportunities for more bullies to return.
Our existance is enough reason for those bullies to return. Fortifications and isolationism will not stop them. Nor will those things help those elsewhere who face the same enemies. We are in a war and we must join with others who also oppose this evil. We must fight it everywhere it exists. Appeasement never works and withdrawing from the world is appeasement.