As a nation of travelers and traders, naval power has long played a central role in the defense of American interests abroad. The oceans bordering North America have been both a barrier and a highway, separating the United States from potential enemies, connecting it to allies, and providing a venue for commerce and trade . Geography dictated the prominent role of naval forces in American foreign policy during the eighteenth and nineteenth centuries, and with the emergence of the United States as a military and economic superpower, Americans have come to depend even more heavily on naval forces as foreign policy instruments.
Randol, Mark A. and Thies, Wallace J.
"The Opportunity Costs of Large-Deck Carriers: Naval Strategy for the 1990sand Beyond,"
Naval War College Review: Vol. 43
, Article 2.
Available at: http://digital-commons.usnwc.edu/nwc-review/vol43/iss3/2