Because the Founders aspired to create a just and equitable government, we have a constitution. In the Revolutionary War, Americans battled for their country's independence from Great Britain. The moment had come to establish a government for the people of the newly formed United States of America after we had won the war.
By dividing the powers of the government so that no one government or organization can control all of them, federalism aims to protect individual freedom. When drafting the Constitution, the Framers used the idea that divided authority was limited power.