The government of the United States is based on the principal of Constitutional supremacy. That is, the constitution is the highest law in the country. Any laws passed anywhere in the country must agree with what is written the constitution. [82-83].
The constitution provides for the United States to have a federal system of government. In this plan, lawmaking powers are divided between two levels of government - the state government and the federal government. The duties of government are then shared between these two levels.
The powers that belong solely to the federal government are listed in the constitution. These powers are called the delegated, or expressed powers. This is because they are "expressed" - written into - the constitution. They include the power to regulate trade and the power to declare war on other countries.
The constitution does not list the powers given to the states. It does, however, set out what powers the states do not have [51-53]. This was done so that states would not take on as much power as they had under the Articles of Confederation. However, through the tenth amendment in the Bill of Rights [94] the people or the states have reserved powers. That is, whatever powers have neither been given to the federal government. For example, state governments can make laws to license automobile drivers and to regulate hunting and fishing.
Governmental powers are sometimes shared by the federal and state governments. These jointly shared powers are called concurrent powers. Road building, dam building, and tax collecting are three examples.