Limits of Power
Presidential, or executive, power is not fixed, and it is limited by both constitutional and political constraints. The Constitution prescribes a system of checks and balances whereby the powers of the federal government are shared among the executive, judicial, and legislative branches.
In this delicate balance, however, the influences of the three branches continually shift. They are determined by the individuals in the various offices and their ability to affect public opinion, and by the political, economic, and social climate of the day.