May 25, 1787 was the day it all began in Philadelphia, as the Constitutional Convention started in earnest and the first votes were taken at what is now called Independence Hall.
By conferring extensive new powers, the Convention gave the federal government full power to levy taxes, borrow money, establish uniform duties and excise taxes, coin money, fix weights and measures, grant patents and copyrights, set up post offices, and build post roads.
The national government also had the power to raise and maintain an army and navy and to regulate interstate commerce. It was given the management of Indian affairs, foreign policy and war. It could pass laws for naturalizing foreigners and controlling public lands, and it could admit new states on a basis of absolute equality with the old.
Perhaps they should have heeded James Madison's warning:
In time of actual war, great discretionary powers are constantly given to the Executive Magistrate. Constant apprehension of War, has the same tendency to render the head too large for the body. A standing military force, with an overgrown Executive will not long be safe companions to liberty. - Portion of speech given by James Madison at the Constitutional Convention, June 29, 1787
Doesn't seem like it was such a good idea to establish a permanent standing army after all, does it?