The framers set up a system not only of separation of powers and not only of a democratized mixed regime, but they also very importantly set up a system of checks and balances where each of the three branches can check and balance the others and what they do. So, for example, Congress has the power of the purse, and the President may be the most powerful man in the world, probably is the most powerful man in the world, but the President literally cannot buy a light bulb for a lamp in the oval office without an appropriation being passed by Congress. So, that's a check and balance that congress has. In contrast, the President has what's called the power of the sword. He is the chief prosecutor in the country. He appoints the Attorney General, he nominates the US attorneys and the deputy attorney general and the assistant US attorneys general. He's also the Chief Military Officer. He's Commander in Chief of the American military. So, the President having the power of the sword and having the power to prosecute has significant powers that he can exercise. He usually has to exercise them through subordinates, and the subordinates usually have to be confirmed by the Senate, and those Senate-confirmed subordinates are often quite a bit more independent of the President than the President would like. There are checks and balances that the Senate has on the president. Senatorial confirmation power and the need for the Senate to ratify treaties, checks and balances the president. On the other hand the president's power to enforce the laws and to pick executive and judicial officers is a check and balance.