Here’s a quote to ponder:
As Montesquieu understood, polities established on extended territories tend to end up as despotisms. They do so for a set of simple reasons. In such a polity, the government is at a great distance from the vast majority of the people it governs. It is out of sight, and, as a consequence, it is largely out of mind. As such, it offers to those in charge a temptation that human beings cannot withstand. They have in their hands Gyges’ ring, and in time it will be used. To this one can add that large polities are subject to frequent emergencies and that this tends to concentrate power in the hands of the central administration.
Montesquieu suggests one antidote and hints at another. He expressly recommends federalism. Federal states can for the most part be governed in the manner of small polities. They leave ample space for citizen participation in decisions of local import. They are also able, because of their size, to defend themselves against large polities. Montesquieu’s prime contemporary example was the Netherlands.
The antidote that he hints at is the separation of powers. Where there are representative institutions, elected representatives can look after the interests of the people. If the legislature is divided between two bodies, they can be set as sentinels over one another. If there is a separate executive power, the man occupying that position can be expected to enforce the laws without prejudice, and this means that the legislators will be subject to the laws they pass (which is a sobering thought apt to encourage prudence on their part). They in turn exercise legislative oversight with regard to the conduct of his ministers in office. Finally, the judicial power (and he has juries first and foremost in mind) protects individual citizens against a tyrannical enforcement of the law on the part of the executive.
All in all the separation of powers — especially that between the legislature and the executive — encourages a healthy conflict within the central government by means of which the two powers guard against one another.
The way our government is structured is not arbitrary. But to so many—especially the younger generations, who are barely taught about what people like Montesquieu said, or assigned to read the Federalist Papers, even in the finest schools—they probably seem that way. If a person hasn’t received any grounding in these matters it makes sense to ask: why limit the federal government? Why have a republic at all? End gridlock! Down with the filibuster! Let’s make it easier to pass bills and issue executive orders so that the central government can solve problems and help us.