Leah Millis / Reuters

The Robert Mueller investigation of Russian interference in the 2016 election embodied the hopes of many Donald Trump critics that defeating the president was possible by disqualifying him personally. Whatever further revelations are contained in Mueller’s full report, Attorney General William Barr’s summary last weekend has already signaled it’s unlikely to be that easy. But, on balance, that’s a good thing for the voices in both parties resisting Trump’s direction for the country. There’s a far better chance of uprooting his influence over the long run if his presidency is ended by the voters, not the courts or Congress.

Trump is such a uniquely galvanizing and polarizing figure, both in his style and his background, that it’s tempting for supporters and opponents alike to imagine that the political movement he has ignited could not exist without him. To that perspective, Trump is the political equivalent of the “one ring” in the Lord of the Rings books. Eliminate him, and everything he’s built will fall into oblivion, the way Sauron, his armies, and even the land of Mordor all vanished in a thunderclap after the ring was destroyed.

But if that was ever true (for Trump, not Sauron), it is clearly no longer so. Trump has demonstrated that there is a substantial audience in the evolving Republican electoral coalition for a message that combines open appeals to white racial resentments and unrelenting attacks on “elites” with an undiluted commitment to the traditional goals of economic and social conservatives—from cutting taxes and eliminating environmental regulations, to opposing abortion and installing conservative justices on the Supreme Court. The appeal of that formula for significant elements of the GOP base would not disappear even if Trump were forced from office by one of the many investigations still swirling around him. Perhaps the only way other Republicans might be discouraged from following Trump’s volatile path is if voters show them that it’s an electoral dead end by repudiating it in 2020.

After the release of Barr’s summary of the Mueller report, such a head-on referendum on Trump’s course now seems virtually guaranteed next year. Trump still faces an array of other legal threats, from federal prosecutors in the Southern District of New York (who have already effectively named him an unindicted co-conspirator in a plot to evade campaign-finance laws), to the accusations of tax evasion, insurance fraud, and sexual harassment from his prepresidential career. And further details from the underlying Mueller report, if and when it’s finally released, seem likely to create additional complications for Trump (if for no other reason than Barr’s letter suggested that Mueller has identified evidence of possible obstruction that has not yet been publicly revealed). But the summary—indicating that the investigation “did not establish” a conspiracy between the Trump campaign and Russian agents—makes it highly unlikely that the president’s critics in both parties will obtain the satisfaction of seeing him removed from office before his term ends.

That’s especially true because senior House Democrats led by Speaker Nancy Pelosi, recognizing the implausibility of winning enough Republican votes for conviction in the Senate, were already dubious about impeaching him.

An electoral rather than legal verdict on this presidency is probably a better outcome for the Trump detractors who consider him a threat to both the rule of law and the nation’s social cohesion. If Trump were compelled to leave office before 2020, through either resignation or congressional action, the majority of his supporters would almost certainly view it as an illegitimate coup by the establishment forces in both parties. And that would allow them to claim that his agenda, tone, and electoral strategy—what could be called Trumpism—had been betrayed, but not defeated.

After Barr’s summary, no one will be able to claim that the GOP has betrayed or abandoned Trump. Instead, the party is locking arms around him even more tightly. Although the attorney general acknowledged that the special counsel found enough evidence for obstruction of justice that he could not exonerate the president from the charge, congressional Republicans this week did not hedge in their bets or establish any distance from Trump pending the full release of the report. Instead, they uniformly declared that the investigation has cleared him. Several, led by Senate Judiciary Chairman Lindsey Graham of South Carolina, immediately pivoted to demanding an investigation into how the Mueller probe itself was launched.

To the longtime conservative strategist Bill Kristol, a leading Trump critic on the right, that reaction offers a chilling preview of how Trump might behave for the remainder of his first term—and in a second one, if he wins it. “For me, the last 48 hours … gives me a tiny hint into what the world will look like if Donald Trump is reelected: totally unrestrained, untrammeled, going after his enemies,” he told me on Tuesday. “It’s also distressing to see how many people are willing to just follow Trump’s lead on this.”

Just as telling as the loud Republican reaction to the Barr summary was the party’s virtual silence at the news that the Trump administration is now seeking to invalidate the entire Affordable Care Act in court. After Democrats made sweeping gains in the 2018 election—largely behind the message that Republicans were threatening voters’ access to health care—many in the GOP had hoped to put the “repeal and replace” debate behind them. But apart from Senator Susan Collins of Maine, hardly any raised public objections (despite private grumbling) when the administration moved this week to overturn the ACA in a case brought by Republican state attorneys general. Nor did many in Congress dissent when Trump proposed to repeal the ACA in his latest budget.

In these ways (and others), the fusion between the party and its volatile president is steadily growing more complete. And that convergence increases the odds that the 2020 election could harden the existing divisions between what I’ve called the Democratic “coalition of transformation”—diverse, younger, white-collar, metropolitan-based—and the Republican “coalition of restoration,” centered on blue-collar, evangelical, and older whites who mostly live outside major urban areas.

With Trump now virtually assured to seek another term after the Barr letter, such a defining election is exactly what the veteran Democratic pollster Stanley B. Greenberg is expecting. He believes that the president has presented Democrats with the opportunity to cement a majority coalition by identifying the GOP so unequivocally with opposition to demographic and cultural change and with an economic agenda tilted heavily toward the interests of the most affluent.

In 2020, Greenberg argues, the electorate could break away from Trump as decisively as it did in 2018. Last year, Democrats captured more than 53 percent of the total House popular vote and benefited from several factors: big margins from minorities and young people, a sharp shift in their direction among well-educated whites, and even modest recovery among working-class whites, especially women distressed by the president’s effort to repeal the ACA. Mueller’s findings, as relayed by Barr, don’t seem likely to defuse that opposition. In a CNN poll released Wednesday, a solid 56 percent of Americans said the investigation had not conclusively exonerated Trump of collusion. An identical 56 percent majority said they are now inclined to vote against Trump for a second term.

With Trump redefining the GOP, Greenberg says, a significant portion of the party’s white-collar support could lastingly break off, like an ice sheet shearing from a glacier. “I think you are going to have a party that goes through a fracturing,” he predicts. Trump’s supporters, of course, expect the opposite: a huge turnout among his core white constituencies that allows him to win the Electoral College, even if he falls short in the popular vote again.

Where both sides might agree is that the results at the ballot box, rather than in any legal proceeding, now look to be the crucial factor in determining whether Trumpism represents a short-term detour rooted in a single (and singular) individual, or a lasting force in American politics. Kristol is one of many Trump critics who acknowledges that, if the president wins a second term, his approach “is pretty embedded at least for a while” as the dominant thrust inside the Republican Party. But if he loses, Kristol said, the conservative critics who believe that Trump’s direction is both morally bankrupt and electorally myopic might find a wider audience inside the GOP. A 2020 loss would not guarantee that Trump’s direction “will be reversed,” Kristol said, “but it’s at least in question.”

The GOP’s reliance on the white voters most uneasy about a changing America ensures that there will always be a substantial constituency inside the party for the backward-looking, racially divisive populism that Trump has synthesized. But a sliver of Republicans still share the perspective of the party’s famous “autopsy” report after Barack Obama’s reelection; that analysis concluded that the GOP must seek to engage with America’s growing minority population rather than try to mobilize more white support by portraying that diversity as a threat, as Trump has done. The sheer weight of demographic change could strengthen the “autopsy” position over time, especially if, through the coming years, it becomes clear that Trump’s approach has alienated too many other voters to win elections, as was the case in 2018.

Even in its truncated form, Barr’s summary of the Mueller report signals that no outside force is coming to undermine Trump’s message by disqualifying the messenger. It was probably a false hope to ever assume that some personal vulnerability on Trump’s part would marginalize his agenda. The assignment facing Democrats and Republicans alike who consider Trump’s vision a unique threat is clearer now than ever: Prove at the ballot box in 2020 that a decisive majority of Americans reject it.

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