President Trump "certainly believes he has the power" to fire special counsel Robert Mueller, Press Secretary Sarah Huckabee Sanders told reporters during a press conference Tuesday.It was the only question related to Mueller that Sanders answered directly, referring most other questions to the Department of Justice or to Trump’s prior statements.She did tell reporters that Trump thinks the investigation has gone "far enough,” and affirmed that the president believes it's within his authority to fire Mueller.Whether he’s right is another question. The attorney general (or, if there is none, the acting attorney general) needs “good cause” to fire Mueller, and Rod Rosenstein, the deputy attorney general who’s overseen Mueller since Attorney General Jeff Sessions recused himself, has told Congress he still has faith in the special counsel. Should Trump ask Rosenstein to fire Mueller, he’s likely to step down in protest.That’s what happened when President Richard Nixon ordered his attorney general, Elliot Richardson, to fire the special counsel in the Watergate investigation, Archibald Cox. And his deputy, William Ruckelshaus, resigned as well. Only the solicitor general, Robert Bork, would fire Cox.The dismissal created a political firestorm — one that led, eventually, to Nixon’s resignation. Any attempt by Trump would almost certainly create a political crisis, too, though Republican Sen. Chuck Grassley of Iowa took it one step further Tuesday, saying it would be “suicide.”