This is interesting because you blame human error or malice on the failure of a reactor causing a potentially global issue. For about 60 years now we’ve had nuclear powered ships without a single issue (with exception to the russian subs rusting and decaying while waiting for decommissioning). Wouldn’t malice or human error be more of an issue here vs a land based reactor? I think most enemies would rather bring down a military naval ship over a land based reactor unless causing terror is their goal. Either way, the reactors generally manage themselves, get replaced every few years but overall are very stable and safe. Nuclear is here to stay in ships and the potential to irradiate the world is much higher when you’re floating in water.