"...While helping develop the atomic bomb at Los Alamos, he entertained himself by figuring out how to break into the safes that contained top-secret research..."

I did not know he helped develop the atomic bomb. That really nice to know that he helped the States obliterate thousands of people who did not need to die afterall.

Many of Feynman's capers and eccentricities are covered in the book "Surely You're Joking, Mr. Feynman!" It's a collection of his essays. I've actually noticed the title pop up a few times before in the comments here in HN. It's a fun read.

The world isn't black and white. Work began on the bomb when there was an existential threat to the country in the form of Nazi Germany.

What little Feynman spoke about the bomb after the war makes it seem like he didn't agree with the way it was used either.

Additionally, many other physicists fought the way it was used at the time.