What prevented the soviet union from making a treaty with western democracies against the nazi threat?

The was mutual distrust between the countries

There was a lot of mistrusts between the soviet union,communism ideology, and democracies of the west and fascism. To the western countries, communism was much more a threat than fascism.  To the fascists Nazis, communism was more of a threat than democracies. to the communist soviet union, Democracy was the greater threat than fascism.

73637 is not the answer cuz i don’t know