Jonathan Ernst / Reuters

President Trump has a coherent theory about American politics that can be summed up in one sentence: Republicans will always come home. Despite the craziness coming from the Oval Office on a daily basis, the president’s decisions and rhetoric have been remarkably consistent, tuned to appeal to his supporters.

Until now, that strategy has worked relatively well—allowing him to retain much of his support, even as he has pushed the envelope rhetorically and with policy. Trump has survived a multitude of scandals and crises by holding the support of the congressional majority and much of the Republican electorate. And this weekend, a Wall Street Journal/NBC poll found that Trump’s approval ratings are up to 47 percent—the best of his term.

Although critics like to paint the president as a television-addicted buffoon who acts according to his latest whim, Trump has absorbed the fact that America is a deeply polarized nation. Whereas other presidents, such as Barack Obama, have tried to push back against partisan divisions, Trump relishes them. In some ways, he sees our political world more clearly than the centrists and unifiers who wish it were different.

The president’s method has pretty strong support from social scientists. The overwhelming weight of recent scholarship points to two major trends in American politics over the past three decades to justify his theory. The first is that partisan polarization in Washington has greatly intensified since the 1960s. The distance that separates the parties on most issues has vastly increased. The ideological homogeneity of each party has solidified. In other words, centrists faded as a major force in politics and policy making. The second and related trend is that the phenomenon has been much more pronounced within the Republican Party. The GOP has moved further to the right than Democrats have moved to the left. Republicans are more ideologically cohesive as a party than are Democrats, who still exhibit greater division and fragmentation relative to their counterparts (although not as much as they did in the 1950s and ’60s, when Democrats were fundamentally divided between southern and northern wings).

During the 2016 election, the power of partisanship was the basis of Trump’s victory. As a candidate, Trump dismissed the pundits who predicted that his full-throated partisan appeals threatened a replay of the 1964 election, when Senator Barry Goldwater’s right-wing extremism persuaded some Republicans to vote for Lyndon Johnson.

In the end, Trump was right; the pundits were wrong. There was very little movement in the electoral map. Although a small number of Democrats voted for Trump in states such as Wisconsin, Pennsylvania, and Michigan, the real key to Trump’s Electoral College victory was that in the final weeks of the campaign—using Hillary Clinton’s email scandal as a perfect foil and capitalizing on Russian social-media hijinks to stir division—Trump whipped up Republican energy behind the ticket. The red states did not turn blue. This was essential, or his approximately 78,000-vote margin in swing states would not have mattered. Faced with the choice between Trump and Clinton on Election Day, Republicans came home.

Trump’s theory of politics has also been crucial to his success on Capitol Hill. The president has depended on the Republican Congress to protect him from investigation and to send key legislative items—such as the corporate tax cut—to his desk for a signature. Though there have been a handful of Republicans, such as Senator Jeff Flake, who enjoy criticizing the president on television, by and large Republicans have voted in unison.

Trump has not left this to chance. He has been extremely aggressive staying on the campaign trail, holding rallies to build his own support and to make sure that candidates in key states understand the risk of opposing him. Many Republican candidates have declared their allegiance to the president as the head of the party. With Trump counting on the fact that Republican legislators will always come home, he has been able to employ a parliamentary governing style, in which the White House and the congressional majority act with a degree of unity that even the late President Woodrow Wilson would have admired.

Now the president is testing his theory for a third time—and it might work again. Many midterm elections go poorly for the party of the president. There is a long list of elections in which the opposition party either gains control of Congress—1946, 1994, and 2006—or at a minimum takes control of one chamber, such as in 2010. This year, the prospects for Republicans seemed even bleaker, given the depth of Democratic anger. It also appeared that many Republican voters were turned off about their commander in chief. But Trump refused to listen. He bet that, in November, Republicans would come home. Since Brett Kavanaugh was confirmed to the Supreme Court, the president has done everything possible to whip Republican voters into a frenzy. He has blasted Democrats as a radical mob, warned of an immigration crisis on the borders, joked about physically assaulting news reporters, and started to take jabs at potential Democratic presidential candidates.

Recent polls suggest that the Trump theory might work in November. There are a number of reports, including from The Washington Post, indicating that the races are tightening. Not only do Republicans stand a good chance of maintaining control of the Senate, but now it seems that Republicans might contain the House Democrats to a slim majority at worst—and that they even have a path to retaining control of the lower chamber. Given everything that Trump has done to shock and awe the nation, bringing radical extremism into the halls of power and mocking cherished government institutions, the recent numbers are remarkable.

The best bet for Democrats to counteract the Trump theory is to implement a comparable strategy of their own. Democratic success in November will depend on mobilizing their own party faithful to come out to vote, and to set aside internal tensions within their party to focus on defeating the Republicans.

In the meantime, those who dismiss Trump’s theory of politics do so at their own peril. Putting aside his recklessness and dismissal of convention, Trump has placed his finger on an essential truth about this political moment. Washington is not in good shape. Extreme partisanship is a reality, not an aberration. The president is not always a first mover in creating political chaos. Rather, Trump is very often responding to the world that Americans have collectively created—and willing to exploit the way it is rather than wish it might be different.

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