One post-war fact about the United States that created tension with the USSR was the United States

The United States had a democratic government.

Explanation:

The United States and the USSR had little to no trust for each other and that was because they both wanted two entirely different things...

The United States focused on freedom and having a democratic government. Americans wanted to be able to choose their future leaders by voting, while also having the option of overruling them if they abused their power or did not do what was in the benefit of the people.

The Soviet Union wanted communism, where essentially the government has control over everything. The USSR not only wanted this, but they wanted worldwide communism and to keep expanding.

While both of them wanted different things, it was hard to get along and come to terms with each other. They both wanted to expand completely different ideas and ideologies.

a is correct

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