Oh yeah because the logic goes like this...
Turkey and Russia argue over whether a single plane shot down was or was not passing over Turkish airspace (it did, though Turkey massively overreacted)........Russia nukes Britain.
....does not compute.
And as **** as our military capability is, there's still MAD, if we didn't empty our subs at their cities in retaliation, it's a great opportunity for the USA to have an excuse.