The Times tries to talk it down:

President Trump on Sunday demanded that the Justice Department open an investigation into whether the department or the F.B.I. “infiltrated or surveilled” his campaign at the behest of the Obama administration, following through on his frequent threats to use his own government to target his political opponents.

Mr. Trump made the order on Twitter during a day of public venting about the special counsel investigation, which he charged had turned up no evidence of collusion with Russia and was now casting a worldwide net so that it could harm Republicans’ chances in midterm congressional elections this fall.

But in ordering up a new inquiry, Mr. Trump went beyond his usual tactics of suggesting wrongdoing and political bias by those investigating him, and crossed over into applying overt presidential pressure on the Justice Department to do his bidding, an extraordinary realm where past presidents have rarely tread.

Rarely? Isn’t it more like never? Or never apart from Nixon? It’s kind of a third rail.

The president’s call came two weeks after he publicly expressed frustration with the Justice Department for failing to give Republican lawmakers documents they are seeking about the basis and findings of the special counsel investigation into whether the Trump campaign worked with the Russians to sway the 2016 election. The president said then that “at some point, I will have no choice but to use the powers granted to the Presidency and get involved!”

But those powers aren’t granted to the presidency.

Legal experts said Mr. Trump’s promise of intervention had little precedent, and could force a clash between the sitting president and his Justice Department that is reminiscent of the one surrounding Richard M. Nixon during Watergate, when a string of top officials there resigned rather than carry out Nixon’s order to fire a special prosecutor investigating him.

“I can’t think of a prior example of a sitting president ordering the Justice Department to conduct an investigation like this one,” said Stephen I. Vladeck, a professor at the University of Texas School of Law. “That’s little more than a transparent effort to undermine an ongoing investigation.”

Into himself.

If Mr. Trump were to follow through with the demand, Mr. Vladek added, “it seems to me that the recipients of such an order should resign — and that we’re heading for another Saturday Night Massacre.”

But a confrontation between Mr. Trump and his Justice Department over the order was not a certainty. It was not clear whether Christopher A. Wray, the F.B.I. director, or Mr. Rosenstein could refer the president’s demand to the department’s inspector general, who is already investigating surveillance of a Trump campaign aide, Carter Page. Such a step could defuse the current crisis and perhaps satisfy Mr. Trump.

We look forward to finding out.