It has nothing to do with the US. I disagree entirely with your suspicion, it's closer to a conspiracy theory than reality.

With regards to the German and Japanese response to Fukushima. It happened to Japan, that explains their emotional response quite easily. Germany could afford to be skittish and shut down nuclear, although with a price to pay for less energy security in the short-term. Not enough of the German economy was powered by nuclear for it to be a terminal threat to their economy.

France can't afford to consider shutting down 70% of their energy generation any time soon. There's a lot less room for emotional debate there. Sure some people can get upset about it, doesn't matter, they're not closing down their economy. The French are not stupid, they're often practical when it's time to be practical; they're fully aware their economy rides on nuclear.