Do you really think that Russia is ready to get into a military confrontation with us?? Take away the nukes from both sides (I am confident that Russia is not willing to go nuclear with us) and they are not even close to being a match for us in any way - especially in a theatre where we would have a massively overwhelming superiority.
And as for their nuclear subs, I suspect that each of them has at least one US attack sub shadowing it very closely that could eliminate the Russian sub on a moment's notice.
A Russia vs US conflict might have been a tossup at the height of their power, but it would be a total mismatch now. More importantly, they know that as well as we do.