Hydrogen is definetly harder to store than ammonia and it takes a lot of energy to compress or liquify it.

It takes a lot of energy to convert hydrogen to ammonia and whatever challenges there are to handling and storing hydrogen, ammonia has its own. At least a hydrogen release isn't a toxic, polluting event.

And I certainly don’t want commercial nuclear ships, because companies will just create “independent” companies that will “mysteriously” go bankrupt once a ship reaches end of life and needs to be decontaminated.

So the taxpayer would have to pay for the decomissioning costs.

Yes. Let's just get ahead of the game and nationalize shipping.