Both participating in the North Atlantic Treaty Organization and joining the United Nations represented a shift in US foreign policy as the United States abandoned its policy of isolationism and became more deeply invested in foreign affairs.
<h3>What is a foreign policy?</h3>
A policy made by a nation indicating its relations with other nations for the period until which such policy is relevant, is known as a foreign policy. The US foreign policy while NATO and UN joining countries was indeed stressful.
At the time of this event, US modified its foreign policy, as it crushed the policy of isolationism and started to involve with other nations and entered into agreements with them to become active in the foreign affairs.
Hence, option D holds true regarding the foreign policy of the United States at the time of the NATO and the United Nations were formed or held.
Learn more about a foreign policy here:
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