yokosuka u.s. navy top officer tuesday say vessels eastern pacific could bring forward reinforce u.s. naval power asia washington contend increase threats region accidents weaken maritime force continue assure meet missions asia pacific area could something come forward third fleet something like meet requirements chief u.s. naval operations admiral john richardson say brief aboard uss ronald reagan carrier japan decline say many ship could transfer grow threat pose north korea ballistic missile nuclear weapon advance couple operations counter china increase military might south china sea part asia put increase burden u.s. seventh fleet add pressure crew blame contribute series accidents involve naval vessels year include collisions two destroyers merchant ship kill 17 u.s. sailors august uss john s.mccain guide missile destroyer strike merchant ship near singapore sister ship fitzgerald almost sink coast japan june collide philippine container ship richardson speak u.s. president donald trump unveil new national security strategy base america first vision single china russia revisionist power part china attempt revise global status quo aggression south china sea u.s. official say beijing build military base manmade islands water claim nations one draw certain conclusion intentions chinese respect islands respond always do go continue present richardson say say north korea urgent task u.s. navy asia become capable every new missile test late ballistic missile test nov. 29 reach altitude 4,000 kilometers 2485.48 miles give enough-range pyongyang claim hit major u.s. cities include washington d.c. richardson say task 2018 build navy lethal dangerous potential u.s. foes near unanimous consensus need naval power say u.s. navy chief say force asia may reinforce warships eastern pacific