In the grand federal budget scheme, earmarks play a relatively small role. So why did South Carolina Sen. Jim DeMint invest such energy and political capital fighting them? A new TIME profile offers one answer:

DeMint and his allies believe the earmark victory is anything but symbolic. They say earmarks are the grease that makes the hidden machinery of money politics work, the bribes that get really expensive measures through Congress. “Appropriators use earmarks to buy support for bills that come in way over budget,” says Brian Darling of the conservative Heritage Foundation. Others point to suspicious coincidences between earmarks for certain industries and campaign contributions from their lobbyists. In DeMint’s typically pointed phrasing, earmarks are “the gateway drug to socialism.”

Which is DeMint’s real target. The earmarks ban is just the first step toward what he hopes will be a radical downsizing of the federal government. That means slashing taxes and spending, repealing the Obama health care law, turning education policy over to the states and gradually dismantling safety-net programs like Social Security and Medicare. All would be blows against what DeMint calls creeping socialism in the U.S.