United States Navy

==Organization==
{{main|Structure of the United States Navy}}
[[File:Organization of U.S. Space Force.svg|thumb|Organization of the United States Navy within the Department of Defense]]

The U.S. Navy falls under the administration of the [[United States Department of the Navy|Department of the Navy]], under civilian leadership of the Secretary of the Navy (SECNAV). The most senior naval officer is the Chief of Naval Operations (CNO), a four-star admiral who is immediately under and reports to the Secretary of the Navy. At the same time, the Chief of Naval Operations is a member of the [[Joint Chiefs of Staff]], which is the second-highest deliberative body of the armed forces after the [[United States National Security Council]], although it plays only an advisory role to the President and does not nominally form part of the [[command hierarchy|chain of command]]. The Secretary of the Navy and Chief of Naval Operations are responsible for organizing, recruiting, training, and equipping the Navy so that it is ready for operation under the commanders of the [[unified combatant command]]s.

===Operating forces===
{{main|List of units of the United States Navy}}
{{further|Structure of the United States Navy#Numbered fleets}}
[[File:USN Fleets (2009).png|alt=Areas of responsibility for each of the United States Navy Fleets.|thumb|Areas of responsibility for each of the United States Navy fleets. [[United States Tenth Fleet|Tenth Fleet]] serves as the numbered fleet for [[U.S. Fleet Cyber Command]] and therefore is not shown.]]

There are nine components in the operating forces of the U.S. Navy: the [[United States Fleet Forces Command]] (formerly United States Atlantic Fleet), [[United States Pacific Fleet]], [[United States Naval Forces Central Command]], [[United States Naval Forces Europe]], [[Naval Network Warfare Command]], [[United States Navy Reserve|Navy Reserve]], [[United States Naval Special Warfare Command]], and [[Operational Test and Evaluation Force]]. Fleet Forces Command controls a number of unique capabilities, including [[Military Sealift Command]], [[Naval Expeditionary Combat Command]], and [[U.S. Naval Information Forces|Naval Information Forces]].

The United States Navy has seven active numbered fleets&nbsp;– [[United States Second Fleet|Second]], [[United States Third Fleet|Third]], [[United States Fifth Fleet|Fifth]], [[United States Sixth Fleet|Sixth]], [[United States Seventh Fleet|Seventh]] and [[United States Tenth Fleet|Tenth Fleets]] are each led by a [[Vice admiral (United States)|vice admiral]], and the [[United States Fourth Fleet|Fourth Fleet]] is led by a [[Rear admiral (United States)|rear admiral]]. These seven fleets are further grouped under Fleet Forces Command (the former Atlantic Fleet), Pacific Fleet, Naval Forces Europe-Africa, and Naval Forces Central Command, whose commander also doubles as Commander Fifth Fleet; the first three commands being led by four-star admirals. The [[United States First Fleet]] existed after World War II from 1947, but it was redesignated the Third Fleet in early 1973. The Second Fleet was deactivated in September 2011 but reestablished in August 2018 amid heightened tensions with Russia.<ref>{{Cite news|url=https://www.cnn.com/2018/05/04/politics/us-navy-second-fleet-russia-tensions/index.html|title=US Navy re-establishes Second Fleet amid Russia tensions|first=Ryan |last=Browne|work=CNN|access-date=16 November 2018|archive-url=https://web.archive.org/web/20181030231709/https://www.cnn.com/2018/05/04/politics/us-navy-second-fleet-russia-tensions/index.html|archive-date=30 October 2018|url-status=live}}</ref> It is headquartered in Norfolk, Virginia, with responsibility over the East Coast and North Atlantic.<ref>{{Cite news|url=https://www.navy.mil/submit/display.asp?story_id=106837|title=Navy Establishes U.S. 2nd Fleet, Vice Adm. Lewis Assumes Command|last=Affairs|first=This story was written by U.S. Fleet Forces Public|access-date=16 November 2018|language=en|archive-url=https://web.archive.org/web/20181005112023/https://www.navy.mil/submit/display.asp?story_id=106837|archive-date=5 October 2018|url-status=live}}</ref> In early 2008, the Navy reactivated the Fourth Fleet to control operations in the area controlled by Southern Command, which consists of US assets in and around Central and South America.<ref>{{cite news |url=http://www.navy.mil/search/display.asp?story_id=36606 |title=Navy Reestablishes U.S. Fourth Fleet |work=Navy News Service |date=24 April 2008 |last=Gragg |first=Alan |id=NNS080424-13 |access-date=30 April 2008 |archive-url=https://web.archive.org/web/20080502014504/http://www.navy.mil/search/display.asp?story_id=36606 |archive-date=2 May 2008 }}</ref> Other number fleets were activated during World War II and later deactivated, renumbered, or merged.

===Shore establishments===
[[File:USS Kitty Hawk at Yokosuka.jpg|thumb|{{USS|Kitty Hawk|CV-63|6}} docking at the U.S. Navy base in [[Yokosuka]], Japan]]

Shore establishments exist to support the mission of the fleet through the use of facilities on land. Among the commands of the shore establishment, {{as of|2011|04|lc=y}}, are the [[Naval Education and Training Command]], the [[Commander, Navy Installations Command|Navy Installations Command]], the [[Commander, Naval Meteorology and Oceanography Command|Naval Meteorology and Oceanography Command]], the [[Naval Information Warfare Systems Command]], the [[Naval Facilities Engineering Command]], the [[Naval Supply Systems Command]], the [[Naval Air Systems Command]], the [[Naval Sea Systems Command]], the [[Bureau of Medicine and Surgery]], the [[Bureau of Naval Personnel]], the [[United States Naval Academy]], the [[Naval Safety Command]], the [[Naval Aviation Warfighting Development Center]], and the [[United States Naval Observatory]].<ref>{{cite web |url=http://www.navy.mil/navydata/organization/org-shor.asp |title=The shore establishment |publisher=United States Navy |website=Navy Organization |date=28 November 2006 |archive-url=https://web.archive.org/web/20150423070709/http://www.navy.mil/navydata/organization/org-shor.asp |archive-date=23 April 2015}}</ref> Official Navy websites list the [[Office of the Chief of Naval Operations]] and the Chief of Naval Operations as part of the shore establishment, but these two entities effectively sit superior to the other organizations, playing a coordinating role.<ref name=":0">{{Cite book|url=https://books.google.com/books?id=xL0qAQAAMAAJ&q=us+military+guide|title=A Civilian's Guide to the U.S. Military: A Comprehensive Reference to the Customs, Language and Structure of the Armed Forces|last1=Schading|first1=Barbara|last2=Schading|first2=Richard|date=22 December 2006|publisher=F+W Media|isbn=978-1-58297-408-8|language=en}}</ref>

===Relationships with other service branches===
====United States Marine Corps====
{{main|United States Marine Corps}}
[[File:F-18A Hornet VMFA-451 USS Coral Sea 1989.jpeg|thumb|A [[United States Marine Corps|Marine]] [[F/A-18]] from [[VMFA-451]] preparing to launch from {{USS|Coral Sea|CV-43|6}}]]

In 1834, the [[United States Marine Corps]] came under the Department of the Navy.<ref>{{cite web |url=http://www.lejeune.usmc.mil/2dfssg/med/files/102.htm |title=Navy and Marine Corps History, Customs, and Courtesies – Fundamentals |website=[[Marine Corps Base Camp Lejeune]] |publisher=[[United States Marine Corps]] |archive-url=https://web.archive.org/web/20120314062316/http://www.lejeune.usmc.mil/2dfssg/med/files/102.htm |archive-date=14 March 2012}}</ref> Historically, the Navy has had a unique relationship with the USMC, partly because they both specialize in seaborne operations. Together the Navy and Marine Corps form the Department of the Navy and report to the Secretary of the Navy. However, the Marine Corps is a distinct, separate service branch<ref name=NSA1947sec606>{{cite web |url=http://global.oup.com/us/companion.websites/9780195385168/resources/chapter10/nsa/nsa.pdf |title=National Security Act of 1947 (As amended 3 August 2007), (50 U.S.C. 426) |date=26 July 1947 |at=§606.(9) p. 69 |access-date=20 June 2015 |archive-url=https://web.archive.org/web/20150213062458/http://global.oup.com/us/companion.websites/9780195385168/resources/chapter10/nsa/nsa.pdf |archive-date=13 February 2015 |url-status=live}}</ref> with its own uniformed service chief – the Commandant of the Marine Corps, a four-star general.

The Marine Corps depends on the Navy for medical support (dentists, [[Medical doctor|doctors]], nurses, medical technicians known as [[Hospital corpsman|corpsmen]]) and religious support (chaplains). Thus, Navy officers and enlisted sailors fulfill these roles. When attached to Marine Corps units deployed to an operational environment they generally wear Marine camouflage uniforms, but otherwise, they wear Navy [[dress uniform]]s unless they opt to conform to Marine Corps grooming standards.<ref name=":0" />

In the operational environment, as an expeditionary force specializing in amphibious operations, Marines often embark on Navy ships to conduct operations from beyond territorial waters. Marine units deploying as part of a Marine Air-Ground Task Force (MAGTF) operate under the command of the existing Marine chain of command. Although Marine units routinely operate from amphibious assault ships, the relationship has evolved over the years much as the Commander of the Carrier Air Group/Wing (CAG) does not work for the carrier commanding officer, but coordinates with the ship's CO and staff. Some Marine aviation squadrons, usually fixed-wing assigned to carrier air wings train and operate alongside Navy squadrons; they fly similar missions and often fly sorties together under the cognizance of the CAG. Aviation is where the Navy and Marines share the most common ground since aircrews are guided in their use of aircraft by standard procedures outlined in a series of publications known as [[NATOPS]] manuals.

====United States Coast Guard====
{{main|United States Coast Guard}}
[[File:Flickr - Official U.S. Navy Imagery - U.S. Coast Guard helicopters land aboard USS Wasp..jpg|thumb|right|A U.S. Coast Guard helicopter preparing to land on the flight deck of the amphibious assault ship {{USS|Wasp|LHD-1|6}}]]

The [[United States Coast Guard]], in its peacetime role with the [[Department of Homeland Security]], fulfills its law enforcement and rescue role in the maritime environment. It provides [[Law Enforcement Detachments]] (LEDETs) to Navy vessels, where they perform arrests and other law enforcement duties during naval boarding and interdiction missions. In times of war, the Coast Guard may be called upon to operate as a service in the Navy.<ref>{{cite web |url=https://www.law.cornell.edu/uscode/text/14/3- |website=[[Legal Information Institute]] |publisher=[[Cornell University Law School]] |title=14 USC 3. Relationship to Navy Department |access-date=28 July 2013}}</ref> At other times, Coast Guard [[Port Security Unit]]s are sent overseas to guard the security of ports and other assets. The Coast Guard also jointly staffs the Navy's naval coastal warfare groups and squadrons (the latter of which were known as harbor defense commands until late-2004), which oversee defense efforts in foreign littoral combat and inshore areas.