New York Times economist Paul Krugman is rehashing a batty idea that former Daily Show host and comedian Jon Stewart mocked him for over eight years ago. In a new blog headlined “Wonking Out: Biden Should Ignore the Debt Limit and Mint a $1 Trillion Coin,” Krugman dusted off an old neo-Keynesian idea of his that he peddled in 2013. He suggested Treasury Secretary Janet Yellen “mint a platinum coin with a face value of $1 trillion — no, it needn’t include $1 trillion worth of platinum — deposit it at the Federal Reserve and draw on that account to...