Christopher Beam is wrong to say libertarians own the heritage of the Founders

In his much-discussed and mostly pretty-good overview of libertarianism for New York Magazine, Christopher Beam makes a statement I think is just flat-out wrong:

Every political group claims the Founders as its own, but libertarians have more purchase than most. The American Revolution was a libertarian movement, rejecting overweening government power. The Constitution was a libertarian document that limited the role of the state to society’s most basic needs, like a legislature to pass laws, a court system to interpret them, and a military to protect them. 

Beam might be right, as far as the Revolution goes. But the people who created and advocated for the adoption of the Constitution weren't really the libertarians of their day. They were trying to consolidate power for a national government, and even gave it unlimited power of taxation! The libertarians of the day were the Antifederalists, who thought that the power of taxation and the ability to create a standing army -- powers granted the government by the new Constitution -- were a dangerous threat to their hard-won liberty. Heck, the reason I even know of the Antifederalists is due to the proddings of a libertarian friend of mine. The Constitution might've restrained the powers of government compared to, say, the British monarchy -- but it was a lot more than limited-government types of the era felt entirely comfortable with. Granting libertarians a stronger purchase on the history of the Founders is simply incorrect.