I don’t think the American governments biggest problem is it’s scope and power: I think it’s biggest problem is inefficiency due to corruption (regulatory capture, etc). It seems to me that the biggest obstacle to fixing this is that many Americans see this as an inevitable character of government rather than something specific to their system, and thus spend their time trying to reduce government (ironically making it even less effective by hobbling it with silly restrictions) rather than fixing it into a well functioning system.