Although you can use your checking account as a reserve account for your cash, much like a savings account, it may not be the best option for that purpose. Most checking accounts do not earn interest, and even those that do typically earn less than a savings account at the same financial institution.
As is the case with other forms of government in American political theory, local governments derive their power from the people; in practice, local governments receive their authorization from their respective states.
The federal government, under the powers of the U.S. Constitution, is given the power to make laws, veto laws, oversee foreign policy and national defense, impose tariffs, impeach officials, enter into treaties, interpret the Constitution, interpret laws and revise laws that allow one state to impede on the rights of another.