Federalism
Another aspect of checks and balances in the Constitution juggles the powers and duties of the federal government and the state governments. The Constitution was written in part because many Americans in the 1780s felt that U.S. government was not strong enough, and lacked sufficient authority to govern the nation. It had no power to raise revenue, but could only request that the separate states contribute their share. The states operated almost like separate nations, framing individual agreements with one another.
In order to remedy this the weakness of the U.S. government in the 1780s, the Constitution grants the federal government the power to raise revenue and to regulate commerce between the states. The states, in turn, are forbidden from passing laws that are contrary to the U.S. Constitution, and are required to give "full faith and credit" to laws passed by other states, and to afford citizens of other states all the privileges and immunities of American citizens.
The system of checks and balances has endured remarkably well for more than two centuries, especially when one considers how much the United States has changed over that time. The nation has grown tremendously and been transformed from a small, rural nation into a vast, industrialized society. The federal government has increased in size and scope, and the presidency has gained extraordinary power in recent decades. There have been many significant struggles between the three branches of government, and between the federal government and the states, in American history, but the Constitution has endured. Indeed, these inevitable struggles were precisely why James Madison created the Constitution's system of checks and balances.