Getting Away with Murder(s)

The story

Almost 1 million people in 22 countries carried out the unprovoked murder of 11 million innocent men, women and children. The Allies knew where a great many of the murderers could be found - Germany, Austria, Italy, the UK, the USA, Canada, Australia, and numerous countries in South America. The Allies unanimously agreed to prosecute those responsible when they drew up The London Agreement in August 1945, but, after the late 1940s, these very same Allies did almost nothing. Why were so many were actively permitted to get away with their crimes?