The very first sentence of the first Article of the Constitution states, "All legislative powers herein granted shall be vested in a Congress of the United States" — making that body the most powerful of the three branches of government. Neither the Presidency nor the Judiciary can make laws — except by usurpations tolerated by Congress. Congress could, for example, prohibit the federal judiciary from issuing usurping rulings in such cases as the infamous Roe v. Wade (abortion) decision simply by exercising its enumerated power to limit the jurisdiction of the federal courts (see Article III, Section 2). Also, Congress could employ its impeachment power in order to tame a corrupt and imperial President.
Here is a listing all of the enumerated powers and duties of Congress.
• Levy taxes.
• Borrow money on the credit of the United States.
• Spend.
• Pay the federal debts.
• Conduct tribunals inferior to the Supreme Court.
• Declare war.
• Raise armies, a navy, and provide for the common defense.
• Introduce constitutional amendments and choose the mode of ratification.
• Call a convention on the application of two-thirds of the states.
• Regulate interstate and foreign commerce.
• Coin money.
• Regulate (standardize) the value of currency.
• Regulate patents and copyrights.
• Establish federal courts lower than the Supreme Court.
• Limit the appellate jurisdiction of the federal courts, including the Supreme Court.
• Standardize weights and measures.
• Establish uniform times for elections.
• Control the postal system.
• Establish laws governing citizenship.
• Make its own rules and discipline its own members.
• Provide for the punishment of counterfeiting, piracy, treason, and other federal crimes.
• Exercise exclusive jurisdiction over the District of Columbia.
• Establish bankruptcy laws.
• Override presidential vetoes.
• Oversee all federal property and possessions.
• Fill a vacancy in the Presidency in cases of death or inability.
• Receive electoral votes for the Presidency.
• Keep and publish a journal of its proceedings.
• Conduct a census every ten years
• Approve treaties, Cabinet-level appointments, and appointments to the Supreme Court (Senate only).
• Impeach (House only) and try (Senate only) federal officers.
• Initiate all bills for raising revenue (House only).
These are the powers of Congress; there are no non-enumerated powers. Leaving nothing to inference, the Constitution even specifies that Congress may pass the laws "necessary and proper" for executing its specified powers. Congressmen have simply to study and apply the Constitution in order to restore sound government. That most fail to do so is not the fault of the Founders, but of the people who elect the congressmen and send them to Washington.