From her home overlooking Setauket Harbor on Long Island's North Shore, a motorboat bobbing at the dock, Stephanie Kelton hopes to revolutionize how the U.S. government manages the economy.

It isn't always a pleasant task.

A key figure in the "Modern Monetary Theory" economic camp, her assertions that the federal government could spend freely for things like a jobs guarantee or Green New Deal without risking runaway inflation, a debt default or a clubbing by global creditors have been Twitter-bombed by mainstream economists as left-wing free lunchism.