Narrow down this question: how did the atomic bomb change military strategies after world war ll

What happened when people started to question traditional christian beliefs?

What would be considered a secondary source about the assasination of abraham lincoln

The picture below shows president richard nixon and the first lady standing before the great wall of china in 1972. they are smiling - as are the chinese with them. when this picture was shown on american television, americans were aware that it was a historic moment. what are two reasons why this moment was important for both china and the united states?