Should private citizens be legally obliged to keep government secrets?

An interesting wrinkle on this issue is the fact that authoritarian governments like China often apply the "state secrets" category very broadly, so that they can punish dissenters and critics while making the government's action look more like an espionage prosecution than censorship. The United States isn't anywhere near that bad, but the risk of this kind of backdoor censorship in the future is something to be wary of.