President Trump speaks to reporters. (Jonathan Ernst/Reuters)

John Podesta, the chair of Hillary Clinton's 2016 presidential campaign, served as counselor to President Barack Obama and chief of staff to President Bill Clinton.

Okay, it's official. President Trump wants to upend 230 years of constitutional history and principle to run the U.S. justice system like a banana republic, or perhaps more aptly like what now passes for the rule of law in the country he aspires to emulate, the Russian Federation.

What the Founding Fathers built with a written Constitution and 85 Federalist Papers, the president is trying to tear down 140 or 280 characters at a time.

For months, Trump has been trying to divert attention from the walls closing in on his former campaign chairman, his former national security adviser and his own son Donald Trump Jr., who are caught up in the investigation by special counsel Robert S. Mueller III. Trump has practiced some of the favorite tactics of his role model Vladimir Putin, labeling any damaging revelation as "fake news" and practicing a refined form of "whataboutism."

I have been one of the favorite targets of the latter. Whenever Trump gets close to Putin, as he did in Vietnam this weekend, and is asked about Russian efforts to help elect him and damage Hillary Clinton by, among other things, criminally hacking my personal email account, he responds by asking: What about the Clintons? What about John Podesta? The Justice Department should look into them.

"Whataboutism" is reliably useful for triggering breathless speculation by the president's allies on Fox News, in the alt-right media and among Russian trolls.

But what appeared to be a typically Trumpian media damage-control strategy has taken a more lawless and sinister turn. This week, it was reported that Attorney General Jeff Sessions — in an apparent effort to appease Trump — is considering appointing a special counsel to investigate Clinton's role in approving the purchase of Uranium One, a company that owned uranium mines in the United States, by Russia's nuclear energy agency. This matter was thoroughly and exhaustively examined by the mainstream media during the 2016 campaign, leading to the definitive conclusion that Clinton played no role.

That didn't stop Trump from pounding his "beleaguered" attorney general, as recently as Nov. 3, to demand that the Justice Department open a criminal investigation of his defeated opponent. And now it appears that Sessions, weakened by the constant attacks from the president he serves, could succumb to that pressure.

In an almost tragicomic echo of Richard Nixon's statement to John Dean, "it's wrong, that's for sure," Sessions in testimony to the House Judiciary Committee on Tuesday said "the Department of Justice can never be used to retaliate politically against opponents, and that would be wrong." Except that seems to be precisely what is going on.

This is what authoritarians and tyrants do. They use the instruments of state power, particularly the wrath of the prosecutor, to rain opprobrium down upon citizens with whom they disagree. It is what Putin did by using the Russian penal system to break the back of Sergei Magnitsky's anti-corruption campaign and end his life. Our constitutional system of limited power, checks and balances and individual rights has protected us from such abuses of power. Trump is putting that system to the test.

The first line of defense against authoritarianism is an independent Justice Department committed to the rule of law. In 1940, Attorney General (and future Supreme Court Justice) Robert Jackson, in a famous speech to U.S. attorneys in the Great Hall of the Department of Justice warned that when "the prosecutor picks some person whom he dislikes or desires to embarrass, or selects some group of unpopular persons and then looks for an offense, that [is where] the greatest danger of abuse of prosecuting power lies. It is here that law enforcement becomes personal, and the real crime becomes that of being unpopular with the predominant or governing group."

Sessions would do well to read the Jackson speech, and I would hope that he has the mettle to stand up to our imperious president. But his conduct in office does not give me much reason for hope.

As a younger man, when I came to work as a trial attorney at the Justice Department, it was impossible to enter the building without seeing the murals that majestically but plainly reminded us of our traditions and our duty. Justice is a hallowed place, if we keep it that way.

But if Sessions yields to pressure from the president and the president's House Republican allies, it will be a dark day at the department I once proudly served. The rule of law will have been weakened, and our country will be in further peril.