Why did Joseph Stalin disagree with how the U.S. and Britain were entering the war

The Soviet Union's proclaimed goal was worldwide communism. Due to this, there had been no trust from the start between the two countries. ... The US feared further encroachment of the USSR and expansion of the "red zone".

this is no the exact answer sorry but this is why he did not trust the U.S Hope this helps

In China the people and the leaders were very careful to keep foreigners out of china. They made sure that all europeans had to get permission in order to preach in china, and also over time, the chinese tried to separate themselves from europe.