The most accurate response regarding American reactions to the end of the Cold War would be: Americans cheered the emergence of democratic governments.
With the collapse of the Soviet Union and the end of the Cold War, many Americans celebrated the spread of democracy in Eastern Europe and saw it as a victory for democratic values and a change in the global balance of power. While some fears of new threats existed, the prevailing sentiment was one of optimism regarding the newfound democratic movements in former communist countries.