The United States is one of eight Arctic nations. Approximately 1,000 miles of the Alaskan coastline border and 200,000 square nautical miles of the U.S. exclusive economic zone are encompassed in the Arctic Ocean. As economic opportunities in the Arctic steadily increase, the U.S. is realizing the strategic importance of the Arctic, but lacks the infrastructure, command and control structure, and Arctic-capable assets to meet national strategic objectives. Since 2009, the U.S. has progressively released strategic documents outlining the U.S. interests and national objectives in the Arctic. Although these documents recognize the increasing interests of the United States in the region, they do not adequately address all the strategic risks at stake in the Arctic and do not provide clear guidance to the Department of Defense (DoD) for defensive lines of effort. The U.S. strategic approach to the Arctic is that of accepting the current stable and conflict free Arctic region as remaining the same in the future. This strategic approach is adequate for the near term; however, it lacks specific guidance to DoD on how to prepare for possible conflict in the future. Recent events involving Russia in the Ukraine and China in the South China Sea provide historical context to the willingness of nations to use military means to defend their national interests. Without adequate defensive posturing, competition over Arctic resources could become the first direct existential threat to U.S. sovereignty. This paper will provide a strategic assessment of the Arctic, from the Department of Defense perspective, and provide recommendations for the combatant commander to prepare defensive lines of effort, should they be needed in 10-15 years or beyond.