The role of the United States military internationally, although diverse in scope and action, is simple in nature and at heart.  To protect and serve the interest and will of the people of the United States and its allies in one form or another. According the National Security Strategy of 2010 (as cited in Kugler, 2011), the United States must maintain its military superiority in the form of tailored deterrence strategies and fully sufficient capabilities across all domains- land, sea, air, and cyber- to reassure allies, contend with threats, and otherwise perform core defense missions. Whether by protecting the freedom of the seas through strength and presence, providing humanitarian aid or disaster relief, or acting as a deterrent of willful aggression, the US military is the force by which the country’s national interest are enforced and protected. 

Domestically, the United States military’s role is more supplementary to government and civilian agencies although the duties it performs are similar in nature to its international ones.  Foremost among them is providing aid and relief from natural disasters and aiding law enforcement by ensuring peace is kept in times of domestic upheaval and turmoil through martial law.  The military also plays a key part in the development and advancement of science and technology through its application of intended military breakthroughs to use in the civilian sector.

The United States military is also a prominent force within the government as well.  Though ultimately led by a civilian, the President of the United States, military officials to the president, such as the Joint Chiefs of Staff, advise and provide options to help better determine how to best utilize the military both domestically and internationally.  Additionally, US military spending and upkeep is a driving factor to the deliberation and drafting of national budgets as well as key discussion points during presidential primaries and elections.

Reference:

Kugler, R. L. (2011). New Directions in U.S. National Security; Strategy, Defense Plans, and Diplomacy: a Review of Official Strategy Documents. Retrieved from https://ebookcentral-proquest-com.proxy-library.ashford.edu/lib/ashford-ebooks/reader.action?docID=3571656&ppg=6

Magnuson, S. (2012). Military Training Technology Making Leap to Civilian Use. National Defense, 97(706), 28-29. Retrieved from https://search-proquest-com.proxy-library.ashford.edu/docview/1039289639/fulltextPDF/CF03BF48D2664581PQ/1?accountid=32521

Stiehm, J. H. (2012). The U.S. Military A basic introduction. doi: 10.4324/9780203128008