Treasury Secretary Janet Yellen warned in a letter to lawmakers on Tuesday that the federal government will run out of money to pay its bills as soon as Dec. 15 if the debt ceiling is not suspended or raised.One idea to ensure the government does not default, even if the debt ceiling is not raised, is to mint a trillion-dollar coin. Yellen has called this a gimmick, but some economists insist it’s a legitimate finance trick that can be used to stave off a default. Axios Re:Cap host Felix Salmon is joined by former U.S. Mint Director Philip Diehl to discuss the idea behind the trillion-dollar coin and whether it’s remotely likely to be minted in the next month.