<P> Former U.S. Navy admirals who head the U.S. Naval Institute have raised concerns about what they see as the ability to respond to "aggressive moves by Iran and China". As part of the pivot to the Pacific, Defense Secretary Leon E. Panetta said that the Navy would switch from a 50 / 50 split between the Pacific and the Atlantic to a 60 / 40 percent split that favored the Pacific, but the Chief of Naval Operations, Admiral Jonathan Greenert, and the Chairman of the Joint Chiefs of Staff, General Martin Dempsey, have said that this would not mean "a big influx of troops or ships in the Western Pacific". This pivot is a continuation of the trend towards the Pacific that first saw the Cold War's focus against the Soviet Union with 60 percent of the American submarine fleet stationed in the Atlantic shift towards an even split between the coasts and then in 2006, 60 percent of the submarines stationed on the Pacific side to counter China . The pivot is not entirely about numbers as some of the most advanced platforms will now have a Pacific focus, where their capabilities are most needed . However even a single incident can make a big dent in a fleet of modest size with global missions . </P> <P> On January 12, 2016, Iranian armed forces captured ten Navy personnel when their two boats entered Iranian territorial waters off the coast of Farsi Island in the Persian Gulf . They were released the next day following diplomatic discussions between the U.S. and Iran . </P> <P> In the middle of 2017, two Navy ships, the USS Fitzgerald and USS John S. McCain (DDG - 56) were involved in collisions with merchant ships during regular transits that results in fatalities . </P>

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