Jeff Sessions is gone. Good. He was a lousy attorney general, who should have been impeached by the House, tried by the Senate, and removed from his position for lying to the Judiciary Committee during his confirmation hearing. Sessions avoided accountability by recusing himself from further involvement with the inquiry into alleged ties between Trump’s business and Trump’s campaign to Russian interests.

The fact that Sessions is no longer attorney general is not a constitutional crisis. But stark indications regarding the motivation for President Trump’s removal of Sessions as the nation’s chief law-enforcement officer—and, make no mistake, Sessions stood down at Trump’s behest—points to a constitutional crisis.

In a move that legal scholars suggest was unconstitutional, the president replaced Sessions with political operative Matthew Whitaker, as part of what Pulitzer Prize–winning journalist Carl Bernstein recognizes as “a coup by the President of the United States against administration of justice and rule of law in the United States.”

Bernstein, who has considerable experience with the abuses of presidential power, is making the right distinction when he focuses on Trump’s efforts to manipulate the response of the Department of Justice to Robert Mueller’s inquiry into wrongdoing by the Trump campaign. “Sure,” the veteran Washington observer says, “[Trump] has the authority to appoint anybody in the executive branch. But the purpose of this appointment is to undermine the special counsel’s investigation, to bury it, to manipulate it, to make sure that he controls it. And that he does not have the authority to do under our constitutional system.”

It is this understanding of the president’s machinations that brought tens of thousands of Americans into the streets Thursday night—from big cities to small towns in states across the country—in what amounted to a truly national outcry against the threat to the Mueller inquiry. This list of communities that responded to the “Nobody Is Above the Law—Mueller Protection Rapid Response” call from a coalition of groups—including Public Citizen, Common Cause, MoveOn, Indivisible, and dozens of other groups—extended from Fairbanks, Alaska to Key West, Florida.

Lisa Gilbert, the vice president of legislative affairs for Public Citizen’s Congress Watch Division, correctly identified the replacement of Sessions on the day after the November 6 election as “a thumb in the eyes of voters.” She said, “Both parties must insist that the investigation be protected from interference. If we are to have a functioning democracy, we must defend the bedrock principle that no one is above the law.”

This premise that “no one is above the law” is hardwired into the American experiment, and it guides us toward the proper response to any move by Trump or Whittaker to undermine the Mueller investigation.

Such a move would spark a constitutional crisis. The right retort to such a crisis has been well understood, and well defined, from the founding of the republic. The Constitution tells us that “The President, Vice President and all Civil Officers of the United States, shall be removed from Office on Impeachment for, and Conviction of, Treason, Bribery, or other high Crimes and Misdemeanors.”

The deliberately vague term “other high Crimes and Misdemeanors” was designed to address a constitutional crises of the sort that arise when a president removes the veteran law enforcement man who is investigating allegations of wrongdoing by that president and his inner circles. It answers the questions posed by George Mason as the Constitutional Convention was deliberating on the question of presidential accountability. “No point is of more importance than that the right of impeachment should be continued,” Mason explained. “Shall any man be above Justice? Above all shall that man be above it, who can commit the most extensive injustice?”

The impeachment power was established to prevent lawless presidents from abusing their authority in order to place themselves above justice. Donald Trump has been abusing his authority since the day he took office. But any attempt to remove Mueller would represent a next stage of abuse that could not be neglected or denied.

Specific acts to undermine or constrain the Mueller probe would demand the submission of an article of impeachment addressing those acts. At this point, it’s clear that there would be resistance to such an article from Republicans, and very probably from cautious Democrats. But this does not change the fact that citizens should demand impeachment. If that demand is heard, hearings by the House Judiciary Committee will follow. If the House were to impeach Trump, and the Senate to try and convict him for obstruction of justice and other high crimes and misdemeanors, his presidency would end.

With Donald Trump’s removal, the constitutional crisis would be finished in precisely the manner that the founders intended. The process is no more complicated than that. It was designed to be simple and sensible. And it remains so. The impeachment of a president who abuses his authority—especially a president who abuses his authority to thwart an inquiry into his own wrongdoing or the wrongdoing of those around him—is not a constitutional crisis. Impeachment is the necessary, and required, cure for the constitutional crisis that begins when a president abandons the rule of law and attempts to make himself a monarch.

John Nichols wrote the foreword to The Constitution Demands It: The Case for the Impeachment of Donald Trump (Melville House) by Ron Fein, John Bonifaz, and Ben Clements.