How did the phrase reinforce Churchill’s overall message in this speech?

The phrase illustrates Churchill's message that Britain and USA should work together against the increasingly aggressive Soviet Union.

The title of his speech was “The Sinews of Peace," but its primary message was that the United States and Great Britain needed to confront  Soviet Union.

Churchill rejected the idea that a new war is inevitable, but he did believe that Soviets wanted to gain the fruits of war by expanding their control through force and doctrines. The only proper response he suggested was to work together to control Soviet expansion.

Churchill’s speech has mixed result, Stalin called his speech as  prime example of racial theory of White Supermacy, while it influenced the Truman administration to think on how to deal with Moscow.

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The phrase illustrates Churchill's message that Europe is divided and the USA must take action against the USSR.

Explanation:

The phrase also creates a mental image that made people fear the Soviet Union. It also made people want to help free/save the people whom were trapped in the "Iron Curtain." Churchill’s “iron curtain” phrase immediately entered the official vocabulary of the Cold War. U.S. officials were less enthusiastic about Churchill’s call for a “special relationship” between the United States and Great Britain.

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