Captain Samuel Nicholas formed two battalions of Continental Marines on 10 November 1775 in Philadelphia as naval infantry.[10] Since then, the mission of the Marine Corps has evolved with changing military doctrine and American foreign policy. The Marine Corps has served in every American armed conflict and attained prominence in the 20th century when its theories and practices of amphibious warfare proved prescient and ultimately formed the cornerstone of the Pacific campaign of World War II.[11] By the mid-20th century, the Marine Corps had become the dominant theorist and practitioner of amphibious warfare.[12][13][14] Its ability to rapidly respond on short notice to expeditionary crises gives it a strong role in the implementation and execution of American foreign policy.[15]
The United States Marine Corps includes just under 203,000 active duty Marines (as of October 2010)[16] and just under 40,000 reserve Marines (as of 2010).[2] It is the smallest of the United States' armed forces in the Department of Defense (the United States Coast Guard is smaller, about one-fifth the size of the Marine Corps, but is normally under the Department of Homeland Security). The Marine Corps is nonetheless larger than the armed forces of many significant military powers; for example, it is larger than the active duty Israel Defense Forces and the active duty British Army.[17][18]
The Marine Corps accounts for around six percent of the military budget of the United States. The cost per Marine is $20,000 less than the cost of a serviceman from the other services, and the entire force can be used for both hybrid and major combat operations;[19] that is, the Marines cover the entire Three Block War. However, these per capita costs do not account for support provided by other branches, such as the Navy's amphibious warfare ships and the long range air transport of the USAF.[20] However given expected defense budget cuts, the Marines may be the service best positioned for "fielding cheap options for an uncertain world."[21] The Marine Corps budget is comparably well handled with a tiny fraction of the Anti-Deficiency Act violations of any of the other three major branches.[22]
http://en.wikipedia.org/wiki/United_States_Marine_Corps
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