Washington Examiner: After watching Mick Mulvaney spar with Sen. Elizabeth Warren, D-Mass., in recent days, it’s tempting to make the modest proposal that President Trump nominate Mulvaney for every administration position that has to testify before Sens. Warren, Cory Booker, D-N.J., Kamala Harris, D-Calif., Chris Murphy, D-Conn., or any of the other senators running for the 2020 Democratic presidential nomination. Mulvaney has earned Warren’s ire because he is the acting director of the Consumer Financial Protection Bureau, which was her brainchild. While she hasn’t backed down in their colorful exchanges, Mulvaney has been winning on points. When the senator lobbed the tired accusation that Mulvaney was forgoing stricter regulations because payday lenders had bought the GOP, (for the record, the payday industry spends about half as much on politics as, say, the abortion lobby ) Mulvaney responded wryly: “Prior to receiving your letter, I never would have thought to consider, for i...