Question

At the Potsdam Conference, who became worried that the Soviet Union would continue to expand its communist control over much of Eastern Europe after WWII?

Answer 1

President Truman who was the then President of the United States feared and was worried that the Soviet Union would continue to expand its communist control over much of Eastern Europe after WWII.

This was because the Soviet Union held Poland and was forcing its communist control on the region which was unacceptable as the spread could spell another war if the Soviet had control of more counties.