Which of the following is a Coast Guard national defense mission?

• A. Maritime interception operations
• B. Military Environmental Response Operations
• C. Port Operations security and defense
• D. Peacetime military engagements

Answer: (C)

Coast Guard national defense missions center on protecting the nation’s ports, waterways, and coastal infrastructure and maintaining readiness to defend those assets. The option that describes port operations security and defense directly targets safeguarding U.S. ports and harbor areas, which are essential national defense responsibilities. This includes securing port facilities, preventing disruption or sabotage, and coordinating with other services to defend maritime approaches during conflicts or emergencies. The other options refer to activities that aren’t focused on defending critical port infrastructure: maritime interception operations are about interdicting illicit shipments and enforcing sanctions, military environmental response operations deal with cleanup rather than defense, and peacetime military engagements describe broader armed conflict activities rather than the Coast Guard’s port-focused defense mission. Thus, port operations security and defense is the best fit.