Why nuclear power is awkward in a battleship

Would nuclear propulsion make sense in a battleship?

He sees it as a poor fit: protecting a reactor inside a combat battleship would impose a major weight and layout penalty.

A reactor is particularly difficult to reconcile with a battleship's need to absorb combat damage. A nuclear plant is a controlled reaction that must remain safely contained while the ship performs the very combat role most likely to expose it to heavy weapons. The concrete, shielding, and armour required to protect the plant would impose a severe weight and layout burden. Submarines and aircraft carriers therefore make a stronger endurance and space case for nuclear propulsion than a gun-armed capital ship.