Ron Johnson Wasn’t Always Like This. The Trump Years Broke Him.

Freedom lovers, rejoice! After much agonizing, Senator Ron Johnson, the Wisconsin Republican, has decided that he will be deferring the joys of retirement to run for a third term this year.

This may not strike some folks as big news. After all, Mr. Johnson is a spring chicken by Senate standards — a spry 66 years old in a chamber that all too often resembles an assisted living facility. But Mr. Johnson, a former plastics executive who rode to power in 2010 on the Tea Party wave of anti-establishment energy, repeatedly pledged to serve only two terms in the swamp.

Like so many citizen legislators before him, however, Mr. Johnson says he failed to anticipate just how desperately Wisconsin voters — nay, the entire nation — would need him at this moment.

“America is in peril,” he declared in an essay in The Wall Street Journal on Sunday. Out-of-control Democrats, aided by media and tech elites, are luring the nation down the path to “tyranny,” he warned. “Countless” concerned citizens implored him to keep up his “fight for freedom,” he noted, “to be their voice, to speak plain and obvious truths other elected leaders shirk from expressing.” What choice does he have but to soldier on?

Claims of national crisis and delusions of indispensability are standard among lawmakers looking to justify abandoning their term-limit pledges. But Mr. Johnson is correct that he has distinguished himself for his willingness to tread where many other officials dare not, at least in the Senate. He has become known as perhaps the chamber’s foremost spreader of absurd yet dangerous conspiracy theories — especially in the areas of anti-vaccine insanity and the election-fraud delusions of a certain former president.

So it is worth drilling down on what sort of “truth” and “freedom” Mr. Johnson is fighting for — and why it would be good news, not merely for Democrats but for all Americans, if he could get his butt whooped in November.

To clarify, Mr. Johnson’s attraction to conspiracy nonsense predates Donald Trump’s lies about the 2020 vote. In the run-up to the election, he used his position as the chairman of the Homeland Security Committee to investigate (read: amplify) unfounded claims about Ukraine and the Biden family that echoed a Russian disinformation campaign. Even his Republican colleagues expressed concern that the inquiry could wind up helping the Kremlin sow discord. The month before his committee released its report, Mr. Johnson received a “defensive briefing” from the F.B.I. warning that he was the target of Russian disinformation — which he said he dismissed because it was too vague and he suspected it of being a political ploy.

Postelection, Mr. Johnson has ardently embraced the Big Lie that the presidency was stolen. Before Democrats assumed control of the Senate, he convened a hearing on the topic. The horrors of Jan. 6 failed to dim his ardor for disinformation. He has both pooh-poohed the seriousness of the attack and indulged wing-nut theories that the violence was the work of “agents provocateurs,” “antifa” and “fake Trump protesters.” He voiced suspicions that the House speaker, Nancy Pelosi, was to blame.

More recently, Mr. Johnson has claimed that the Democrats cannot be trusted — because, you know, election fraud — and urged Wisconsin’s Republican-controlled Legislature to seize the authority for overseeing voting from the state’s bipartisan elections commission.

Pressing a partisan power grab based on partisan lies to rig the electoral system — that is how committed the senator is to truth and freedom.

As much of a threat as he is to American democracy, Mr. Johnson may be a bigger one to the health of the American people. Since the arrival of the coronavirus pandemic, he has talked down its seriousness, at one point charging that Dr. Anthony Fauci had “overhyped” Covid-19.

On the vaccine front, the senator has been a font of misinformation and scaremongering, misrepresenting data and bungling basic facts. He has conveyed considerably more enthusiasm about unproved treatments like horse de-wormer and mouthwash than for proved vaccines. YouTube twice suspended his account for violating its medical misinformation policy.

All told, when it comes to spewing dangerous drivel, Mr. Johnson has displayed a commitment and creativity rarely seen outside of QAnon gatherings or Trump family dinners.

RonJon wasn’t always like this. He used to be a relatively straightforward pro-market, small-government, budget-conscious conservative. He seemed to have a more or less solid grip on reality. But the Trump years broke him, as they broke so many in the Republican Party.

The people of Wisconsin are not impressed. Polling suggests the senator is about as popular there as Brett Kavanaugh at an Emily’s List happy hour. The editorial board of The Milwaukee Journal Sentinel declared him “the most irresponsible representative of Wisconsin citizens” since Joseph McCarthy.

Even so, the senator has the electoral edge. Historical trends are on his side, as is the power of incumbency. Democrats will need a strong nominee, a savvy strategy, piles of cash and a whole lot of luck to unseat Mr. Johnson. A dozen Democratic challengers are vying to make the attempt, led by the state’s lieutenant governor, Mandela Barnes.

Mr. Johnson is the lone Republican senator up for re-election this year in a state carried (barely) by Joe Biden in 2020. This alone would make him a mouthwatering Democratic target. As an exemplar of Trumpism, he is downright irresistible — a particularly toxic test case of the former president’s enduring hold on the Republican Party.

Do the nation a solid, Wisconsin: Commit to helping Mr. Johnson stick by his original promise to serve only two terms. After everything it has been through lately, America shouldn’t have to suffer through another six years of his twisted take on truth and freedom.

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