That's not an apples-to-apples comparison. Naval reactors look cheap, because the cost is for the reactor in the narrow sense. Other major costs, such as the containment building and countermeasures against natural disasters and terrorist attacks, are included in the costs for the rest of the ship.

> How much of this is based on how expensive it is to bring a powerplant online? How much of that expense is based on endless lawsuits from environmental groups and weaponized environmental laws? Why can the navy without those restrictions build safe reactors for ~$2million/megawatt?

Pretending it's all the fault of the bad environmentalists is a bit ridiculous. A nuclear powerplant is a tricky thing to create. A lot of projects had delay, often not due to any environmentalists or anti-nuclear people, but because the parts failed their internal control, which demonstrates that it is tricky to build. A nuclear powerplant is a huge provider that cannot be turned online for usually ~10 years, so you can also understand the complexity and the uncertainty: we are not able to predict the price of electricity or what will the electricity grid will look like in 2-3 years, and yet they need to predict it for a given region in 10 years.

And some environmental laws are frivolous or turned out the be incorrect (the same way some people who at the time were against some environmental laws turned out to be incorrect years later), but some laws are just legitimate and it is simply not fair to pretend that the opinions of some people should just be discarded because you have a different opinion. I myself don't always agree with some law, sometimes anti-nuclear, sometimes pro-nuclear, but a given fraction of these laws will exist, it is just the reality. It's like saying "communism would work if it was not for people who don't like communism": people who don't like communism will always exist and if your model require a world where it is not the case to work, then your model is stupidly unrealistic.