Endurance, not just output, in nuclear warship power

What makes nuclear power useful for railguns and lasers at sea?

Its main advantage is the ability to sustain high power and recover it quickly, rather than merely producing a higher one-time output.

The discussion distinguishes instantaneous power from endurance. A conventional steam plant of similar size may produce comparable power at a given moment, but it cannot maintain maximum output indefinitely without fuel logistics. For submarines, nuclear propulsion also removes dependence on atmospheric oxygen. For surface combatants, the main advantage is sustained high output and the ability to spool that power up quickly. Those characteristics suit prospective railguns and lasers, especially when reactors are paired with capacitors that store energy between shots.