The most accurate, currently used ICBMs can have a CEP ranging from 10 to 130 meters so they can probably be used that way. Most ICBMs also have a configurable "detonation" height, meaning they can probably be set low enough to severely damage a nuclear plant reactor containment building. Not sure if they are powerful enough to vaporize the fuel rods though.

But as you said, at that point, it wouldn't really matter anymore.

Did you reply to the right comment?

I read quite a few of Patrick Robinson's submarine related fiction.

It gets a bit tiring towards the later books, but I recall the earlier ones were quite good.

https://www.goodreads.com/author/show/8979.Patrick_Robinson

There's always the classic Hunt for Red October.

You must have read "The Hunt for Red October".

I'm told by ex-(Submarine Commander)s and ex-submariners that it's surprisingly accurate, and one even said that it's used in training. If you read it carefully enough you can plot the positions of the boats throughout.

Definitely better than the film, although the film is excellent.

Joe Buff's Jeffrey Fuller series starting with Deep Sound Channel.