Americans thought the USA had a moral mandate because it was incrementally less bad than Nazi Germany and the Soviet Union. This was actually a common opinion. It's going to be amusing when the United States rots and collapses in the same basic way as the USSR only 40 years later
America: The only place so confused about the nature of value that they think morality is something you can spend and then get back. At least every other country had some notion of amoral superiority. Americans just think police brutality comes out of a bank account.