[handrous]

> especially nuclear-armed ones.

I took "nuclear sub" to mean "nuclear powered" (as opposed to e.g. diesel-electric, which are still fairly common), which I think represents a somewhat larger set of submarines, outside the US, than just the set of all non-US "boomer" (nuclear-armed) subs. That is, attack subs without nuke-tipped missiles can still be nuclear subs because they have a nuke plant onboard for power.

[Eelongate]

The submarines in question, Seawolf class SSNs, have nuclear reactors but not nuclear weapons.

[KineticLensman]

Agree - it's not actually clear which type is meant. If boomers then this is a indeed very small number (e.g. only four for the UK, which is one of the few non-US countries (four?) to operate boomers).