Under the Articles of Confederation, the national government lacked the important power to impose taxes. This limitation severely restricted its ability to raise funds for national needs and obligations, such as paying debts from the Revolutionary War or maintaining a military. The government could only request money from the states, which often did not comply fully, leaving the central government chronically underfunded. In addition to lacking taxing power, the national government could not regulate commerce between states, enforce laws directly on citizens, or compel states to send troops or financial contributions. These weaknesses contributed to the ineffectiveness of the government under the Articles and ultimately led to their replacement by the U.S. Constitution.