I have thoughts on subs at WPR:
But the perceived effectiveness of submarines as an area-denial weapon in some ways led to their emergence as power-projection platforms. The threat of enemy submarine attacks can make a navy wary of dispatching aircraft carriers or surface warfare vessels on strike missions. In such an environment, however, submarines can still carry out strike missions at relatively little risk to themselves. The conversion of four Ohio-class ballistic-missile submarines into cruise-missile platforms represents one manifestation of such a shift to conventional offensive strike capabilities, whose effectiveness wasdemonstrated by the performance of USS Florida during the Libya operation. This shift means that even as countries like Iran build their anti-access capabilities in part through expanding their submarine forces, the United States and the United Kingdom retain difficult-to-counter strike assets.