article_snippet.sent: (CNN)Silently moving deep beneath the ocean's surface, combat submarines can employ the element of surprise to carry out devastating attacks on naval fleets and land targets.
article_snippet.sent: For decades, the U.S. military has maintained the U.S. military dominance in the depths of the world's oceans by boasting the most technologically advanced submarine fleet.
article_snippet.sent: However, officials say China and other nations are rapidly expanding the size and scope of China and other nations own submarine forces.
article_snippet.sent: And, according to a report by the Center for Strategic and Budgetary Assessments, U.S. Navy must rethink the role of manned submarines and prioritize new underwater detection techniques.
article_snippet.sent: We know they are out experimenting and looking at operating, and clearly want to be in this world of advanced submarines," Vice Adm. Joseph Mulloy told the House Armed Services Committee's sea power subcommittee in February.
article_snippet.sent: Mulloy, who is deputy chief of naval operations for capabilities and resources, says Chinese submarines are still technologically inferior to those used by the United States, but that margin of difference is shrinking.
article_snippet.sent: Concern that China could match U.S. Navy underwater capabilities in the near future has encouraged the development of an unmanned drone ship to independently track enemy ultra-quiet diesel electric submarines over thousands of miles to limit thousands of miles tactical capacity for surprise.
highlights_snippet.sent: U.S. Navy is developing an unmanned drone ship to track enemy submarines to limit U.S. Navy tactical capacity for surprise .
  
highlights_snippet.sent: Advances are necessary to maintain technological edge on Russia and China, admiral tells House panel .