WASHINGTON — The separate convictions of President Donald Trump’s former campaign chairman and his legal fixer tear the facade of respectability off a White House engulfed in a Mafia-like enterprise, imperiling his presidency.

Longtime political operative Paul Manafort, who ran Trump’s 2016 national convention team, and Michael Cohen, Trump’s personal lawyer who paid hush money to women who claimed having sexual affairs with the president, now face long prison terms. Cohen particularly fingered Trump as having collaborated in the payoffs.

Trump, meanwhile, remains legally unaffected but still in the sights of the Mueller investigation into alleged Russian elections meddling closing in on him. This is so despite his repeated assertions there was “no collusion” by himself or his campaign, and that the two convictions have nothing to do with what he labels “a rigged witch hunt” against him.

The whole business stinks to high heaven, as Trump brazenly labors to discredit special counsel Robert Mueller and the entire FBI tenaciously gathering incriminating evidence supporting charges of conspiracy.

Beyond the prospect of further court actions against the president and his makeshift political and governmental operations, the mask of normalcy compared to all previous presidential administrations has been stripped away from Donald Trump Inc.

The convictions or guilty pleas now include, beyond Manafort and Cohen, former National Security Adviser Michael Flynn, Manafort’s chief aide Rick Gates, political adviser George Papadopoulos and others in a phalanx of liars, dissemblers and artful dodgers worthy of any common street gang.

Trump’s attorney general, Jeff Sessions, has offered a B-movie version of a smarmy underling who voluntarily escaped his responsibilities by recusing himself on grounds he was a onetime Trump campaign aide and toady. Only recently has he stood up to Trump’s incessant criticism of his failure to quash the investigation.

Trump’s latest lawyer, the once-respected New York Mayor Rudy Giuliani has bent himself into a pretzel trying to build a ludicrous defense for his client, repeating his empty “no collusion” mantra and standing truth on its head.

Giuliani has tried to dismiss the Mueller investigation as “somebody’s view of the truth, not the truth,” adding incomprehensibly that “truth isn’t truth.” Not since Trump counselor and chief propagandist Kellyanne Conway’s invention of “alternative facts” has such gobbledygook passed as straight talk.

It should be abundantly clear by now that the reins of power in the world’s greatest democracy have fallen into the hands of a demagogue who has little regard for or awareness of the legitimate and ethical responsibilities involved in leading it.

It is not too much to say that the immense task of putting the nation back on track as a beacon of hope and justice is now on the shoulders of Mueller and his investigators, to free it of the plague of this unprincipled, ignorant and reckless misfit.

As Trump strives to undermine that imperative task by doing whatever he can to discredit Mueller personally and the country’s long respected law-enforcement agency, the very pillars of American justice are seriously threatened.

As long as the Republican Party that Trump has taken over as his own remains in control of Congress, the prospect of impeaching him in the House for high crimes and misdemeanors the Senate convicting him is far from certain.

The question whether a sitting president can be subpoenaed or convicted of a crime also remains for the Supreme Court to decide, with the confirmation of a fifth conservative, Judge Brett Kavanaugh, now seen as likely.

Consequently, the November congressional midterm elections will be not only a referendum on Trump’s presidency but also on its very survival under the dark cloud that has enveloped our democratic process.

In a bizarre way, Trump continues to be an unintentional helpmate to his critics. By denying the undeniable and continually lying and slandering Mueller and the FBI, he only reinforces their case against him.

Trump’s and Giuliani’s insistent calls for Mueller to wind up his methodical gathering of evidence and end the whole business that so plagues this irresponsible president reflects their own dread of what it will reveal.

Meanwhile, the country also awaits the verdict on how much longer aberrant presidency will go on.

Editor’s note: Jules Witcover’s latest book is “The American Vice Presidency: From Irrelevance to Power,” published by Smithsonian Books. You can respond to this column at juleswitcover@comcast.net.v