The president of the United States is now at the center of an obstruction-of-justice investigation by the FBI. There can be no other conclusion after last week’s guilty plea by former national security adviser Michael Flynn and the bewildering statements made in the past few days by President Donald Trump.

This is a perilous time. Regardless of your feelings about Trump and whether there is evidence that he broke any laws, there is a great risk to his attempts to undermine our independent system of justice.

Firing special counsel Robert Mueller, who is conducting a legitimate and serious investigation, would bring disastrous consequences. So would a pardon of Flynn to stop him from telling the FBI what he knows, information that will enable prosecutors to determine whether anything more than rank incompetence resulted in improper contacts with Russia and the firing in May of FBI Director James Comey.

Trump continues to lash out at the FBI and the attorney general, and to demand that the Justice Department open criminal investigations of his political opponents. A statement Trump tweeted Sunday encapsulates it all: “After years of Comey, with the phony and dishonest Clinton investigation (and more), running the FBI, its reputation is in Tatters — worst in History! But fear not, we will bring it back to greatness.”

In mistakenly venting his frustrations and worries about the special counsel’s probe, Trump is turning to the playbook that made him a successful candidate — the twisting of facts, discrediting of the media, and undermining of intelligence and investigatory agencies.

Remember, Richard Nixon, Ronald Reagan and Bill Clinton were all investigated by some version of a special counsel for obstruction of justice. Only one, Nixon, tried to use the CIA to interfere with the FBI’s efforts to follow the money. He fired special prosecutor Archibald Cox and ransacked the Justice Department, all of which led the House Judiciary Committee to approve obstruction of justice as its first article of impeachment. Nixon resigned before a full impeachment vote in the House, but Watergate left the nation reeling for decades.

Any finding by Mueller that the president obstructed justice would be deeply troubling for the nation. If the president prevents us from finding out what happened, it would be even worse.