The question posed by our friends in big hats is "where are all the threat submarines now?" Most of the USSR's old subs are rusting alongside. They've made a bomb out of exporting Kilo's but they've mostly gone to places that aren't really going to be a threat to us (I think). Besides diesel/electric is mainly for littoral warfare (standing by for correction), how useful is MR2/ will be MR4 in those areas? I know a lot of work has been done in improving capability in that area but how much???