> One common question is, why not fission? Fission works technically, but not practically. Small Modular Reactors (SMRs) could power ships, but licensing fission reactors on land is already brutally hard and expensive—doing it for vessels moving between international ports with enriched uranium is nearly impossible

What makes you think that licensing a fusion reactor will be easier? Safely handling tritium is fantastically more complicated that the fuel of a fission power plant.

Also, do you plan on breeding your fuel aboard the ship? If no, how do you plan to produce, store the tritium and refuel the ship? If yes, I'd like to know how you are planning to host the massive chemical plant to purify coolant, recycle unburt fuel, separate isotopes, detriatiate water and refuel that comes with your tokamak.