Final answer:
The function of government most concerned with protecting a nation's people from external threats is ensuring national security.
Step-by-step explanation:
The function of government most concerned with protecting a nation's people from external threats is ensuring national security. National security refers to the measures taken by a government to protect its citizens, territories, and interests from external threats such as terrorism, military invasion, or espionage.
For example, a government may establish a strong military, implement border control policies, and form international alliances to ensure national security. These actions aim to safeguard the country and its people from potential harm or danger.
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