Well...yeah. The national labs do fusion experiments because they can't do bomb tests any more. (It's also the reason they tend to have the biggest supercomputers in the world, so they can simulate nuclear explosions.) But that doesn't mean they don't learn things that might be useful for energy production.
The test ban treaty was a slick example of pulling up the ladder after arriving somewhere first. Want weapons research? Now you need weapons researchers and supercomputers...
