Answer:
Because the US Constitution created a strong central government and did not provide for specific protections of people's liberties.
Step-by-step explanation:
The Anti-Federalists constituted a political coalition that emerged during the debates to ratify the Constitution. They were the group that firmly refused to its ratification believing that it gave too much power to the central government and did not specifically protect individual rights and, therefore, was a threat to liberty. The Anti-Federalists, instead, insisted on the adding of a Bill of Rights that specifically guaranteed basic individual liberties such as the right to express, to due process, to have a fair trial, among others.