Subscribe for 99¢

When you strike at a king, you’d best not miss, goes the old adage. It shouldn’t apply in a democracy — yet it explains why the Justice Department has launched a criminal probe into the origins of the Russia investigation. The probe isn’t about justice; it’s about President Donald Trump seeking revenge against those who dared ask legitimate questions about his campaign’s suspicious activities relating to America’s top global adversary.

If this probe is granted political legitimacy, any attempt to investigate future presidential wrongdoing would risk provoking the wrath of the nation’s top law-enforcement agency. In real ways, this revenge move is among the most dangerous actions Trump has undertaken.

Trump’s history of punching down at perceived enemies and trading in loopy conspiracy theories long predates his ascension to the White House. When he first took office, many assumed that the presidency would normalize him. He has, instead, ab-normalized the presidency.

The willingness of other Republicans to indulge Trump’s persecution fantasies makes this situation doubly dangerous. Take, for example, their probe of individual voter fraud — a non-existent GOP boogeyman that nonetheless became the subject of an entire commission investigation based on nothing but Trump’s self-serving desire to explain his popular election loss to Hillary Clinton.

Attorney General William Barr’s latest probe is essentially the same animal. What started as a review of how the Justice Department handled the Russia investigation — in itself, a perfectly valid issue for departmental self-review — now has reportedly escalated into a criminal probe. There has been no public explanation for the change, but given Trump’s history, the president almost certainly is latching onto more conspiracy theories from the right-wing fever swamps.

A favorite GOP obsession revolves around the so-called Steele dossier: a report from a former British intelligence officer alleging Russian collusion with the Trump campaign. Trump’s defenders have made much dark hay of the fact that Clinton’s campaign was among those commissioning the investigation — while shrugging off far more shocking facts, like Trump’s campaign meeting with Russian operatives, his public call for Russia to interfere in the election, or his firing of the FBI director to halt the investigation into his campaign.

None of those events is disputed. They cried out for investigation, which was what the Russia probe was all about. But Barr — as usual, serving Trump’s whims instead of his sworn duty to the nation — ran interference to convince America the final Russia report was exonerating rather than damning.

Now Barr is attempting to set the dangerous precedent that if an investigation, no matter how warranted it is, fails to bring down a president, the investigators themselves will be subject to revenge-minded criminal liability. This is truly banana-republic stuff, and no responsible elected official in either party should treat it as anything else.