Sen. Elizabeth Warren and Tesla CEO Elon Musk.Patrick Semansky-Pool/Getty/Patrick Pleul/picture alliance via Getty Images Sen. Elizabeth Warren spoke to tech journalist Kara Swisher about her spat with Elon Musk. Musk called Warren "Senator Karen" in December after she said he pays too little tax. Warren told Swisher: "What he's hoping for is that this is personal." Sen.