The word around Moscow is that the crew of the two Akula class subs recently detected off the coast of North America, will not be hailed as heroes when they return home. While this is the first time Russian subs have operated in the western Atlantic in over a decade. Apparently, they were supposed to go there, and return, undetected. That's how it's done in the submarine business. This is particularly true if you are sending two of Russia's latest, and most difficult to detect, boats.
But the Americans detected the Akulas, using an underwater detection system built during the Cold War, when revealing what it found was not done (lest the Russians use that knowledge to develop better ways not to be detected). Why was that not done this time? Well, for one thing, the Cold War is over. Then there's the need to convince Congress and the taxpayers that all the billions spent on tracking foreign subs, is still worthwhile. These two subs are now being tracked by Canadian anti-submarine aircraft, who haven't had this kind of training opportunity since the early 1990s.
A similar tracking system is operating in the Pacific, but you rarely get reports of Chinese subs being detected. In the Pacific, that's considered information useful to the enemy.