Banning the Benjamin would strip Americans of a layer of privacy and a currency of convenience. It's being advanced as a war measure to make it harder for terrorists to carry cash. But it's a smokescreen for the fact that the Democrats are out of ideas on both the economy and national security. The putsch against the Benjamin is being sprung by Lawrence Summers. He was President Bill Clinton's treasury secretary and also a president of Harvard. He came within a whisker of being chairman of the Federal Reserve under President Obama. Mr. Summers wrote up his idea in the...