that's fucked either way they shouldn't have more power than the elected president
The central tenant of the system is a series of checks and balances between power-holding bodies of various size and source:
- Only the legislative branch (Congress) can make laws. Elected by the people for 2- or 6-year terms and can be re-elected infinite times.
- The executive branch (President) can veto those laws. Congress can then overturn his vetos, but the President can sort of make his own laws (executive orders). Elected by the people as well to a 4-year term and no more than two terms.
- The judicial branch (Supreme Court) enforces these laws and can overrule them. Appointed for life by the President.
The President has the most authority/autonomy of any one individual (a single Congressperson or Supreme Court Justice can't do much) but is limited by the checks I described above. It's not perfect but we do have the longest uninterrupted stretch of peaceful transfers of power in recorded human history, so I think it's worked out relatively well all things considered.