The PWR tech was chosen by the US government originally because using that type of reactor supported weapons production. Many countries still want it for that

The PWR tech was chosen by the US government originally because using that type of reactor supported weapons production. Many countries still want it for that reason. Newer types aren't used yet in the US because the incredible over-regulation of existing reactors due to the fear involved has made them very un-economical to build and very difficult to get new designs approved... if there's no money in something, corporations won't do it.