[authatheist]

You know that governments tend to abuse their power over us, so you want one arm of the government to keep the other one in check? One head of the Hydra will prevent the others from biting you?

The US is a prime example of how a limited government just doesn't stay limited. Words on a piece of parchment don't actually prevent psychopath rulers from abusing us. The USSR had a constitution too, and it "guaranteed" free speech just as well as any other constitution would, ie. not at all.

There's no political solution to the abuses caused by an arrangement of rulers vs subjects. The only way to improve things is to realize we should not have rulers at all.