macing after the uss john s. mccain collided with an oil tanker off of the coast of singapore. this is the fourth incident involving u.s. warships in the pacific just this year. the second collision in just over two months. a reminder these are the naval forces monitoring the grave threat right now from north korea. retired rear admiral john kirby, now a cnn national security analyst. truly amazing events here. how can you explain this series of accidents? that s the thing, i don t think we can. we need to be careful we don t try to you saw the head of the navy come out and say i don t know if we have a systemic problem here or not. i don t know if we have a fleet