Final answer:
The United States engaged in the Berlin Airlift, created NATO, and built up arms to respond to Soviet aggression and expansionism during the Cold War, protecting Western nations and deterring the spread of communism.
Step-by-step explanation:
The actions such as the Berlin Airlift, the formation of NATO, and the buildup of arms, including nuclear devices, were taken by the United States in response to Soviet aggression and expansionism (Option C). Following World War II, there was intense rivalry between the US and the Soviet Union, leading to the Cold War. To protect Western Europe from potential Soviet invasions and to prevent the spread of communism, the US engaged in numerous initiatives including the Berlin Airlift, forming NATO for mutual defense, and escalating nuclear capabilities as a deterrent.
NATO, specifically, was created to protect Western countries from Soviet aggression and ensure collective security among participating nations. The Warsaw Pact was established by the Soviet Union in response to NATO as a means of securing the communist nations of Eastern Europe. This historically significant period saw the division of Europe into Eastern and Western Blocs along ideological lines, with the US and its allies on one side, and the Soviet Union and its satellite states on the other.
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