Final answer:
The U.S. Fleet Forces Command serves as the naval component of NATO, whose key focus is defense among its members and maintaining peace in Europe.
Step-by-step explanation:
Part of the mission set of the U.S. Fleet Forces Command is to serve as the naval component of NATO, the North Atlantic Treaty Organization. NATO is a military alliance that includes both North American and Western European states. It was formed in 1949 for the purpose of deterring Soviet military aggression, assuring mutual defense among member states, and maintaining the peace and stability of Europe. With the end of the Cold War and expansion of its membership, NATO's role evolved to include intervention in international crises and peace-building efforts in regions such as Kosovo and Afghanistan.