I really think it’s a mistake to take them down. If anything, convert ‘em to nuclear power and upgrade them. I think we’ll be needing them very soon. I have a feeling we’re going to lose a few carriers in the near future and you just can’t put one together quickly.
Physically impossible to convert to nuclear power.
Old ships are old ships. There's a point where it's not worth it to repair or upgrade them.
You can't change engine rooms nuke to conventional or vice versa once the keel is laid. That said they should mothball but not sink it or the JFK. In a pinch the boilers could be re-tubed the steam lines replaced and pressed into service.
You can also train and qualify a conventional crew much quicker than a nuke. In event of loss of one or several carriers KH and JFK could be put back into commission probably in about 18 months which is quicker than a nuke or conventional could be built.
Our other ships from Mothball Fleet besides the CONNIE are from the Forestall Class.