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There's a whiff of Weimar in the air. During the years of the Weimar Republic (1919-33), Germany was threatened by Communist revolutionaries and Nazi uprisings. Foreign Minister Walter Rathenau was assassinated, and violent street fighting was commonplace. Then Adolf Hitler took power in 1933.

America is nowhere near that point. But many surely agree with The American Interest's Jason Willick, who wrote Sunday that "this latest round of deadly political violence has" him "more afraid for" the United States than he has "ever been before."

But as he pointed out, this political violence -- identity politics violence is a more precise term -- began well before Saturday's horrifying events in Charlottesville, Virginia, and before the election of Donald Trump. Examples include the June 2015 murder by a white racist of black churchgoers in Charleston, South Carolina, and the July 2016 murder by a Black Lives Matter sympathizer of five police officers in Dallas.

This year, we've seen a Republican congressional candidate shove a reporter in Montana and a Bernie Sanders booster shooting at a congressional Republican baseball practice and seriously wounding House Majority Whip Steve Scalise in Alexandria, Virginia.

In Charlottesville, there were multiple bad actors. White nationalists and neo-Nazis uttering vile racism demonstrated against removal of a Robert E. Lee statue. One drove a car into a crowd -- killing one young woman and injuring about 20 others -- a tactic of Islamic terrorists.

Many so-called antifa (anti-fascist) counter-demonstrators, some disguised with masks, attacked the Lee statue supporters with deadly weapons. "The hard left seemed as hate-filled as alt-right," tweeted New York Times reporter Sheryl Gay Stolberg from Charlottesville. "I saw club-wielding 'antifa' beating white nationalists being led out of the park."

As Stolberg noted, the police not only failed to separate the two groups but maneuvered them into direct and predictably violent confrontation. Antifa believe that hateful words are violence and that they're entitled to be violent in response, as they have been on campuses from Berkeley to Middlebury -- a view profoundly at odds with the rule of law. "The result," writes Peter Beinart in The Atlantic, "is a level of sustained political street warfare not seen in the U.S. since the 1960s," led by a group that is "fundamentally authoritarian."

President Trump was widely criticized -- by many conservatives, as well as liberals -- for his Saturday statement condemning "this egregious display of hatred, bigotry and violence on many sides" without specifically denouncing white nationalism. Barack Obama faced much less criticism in July 2016 when he lamented the Dallas police murders but went on to decry "the racial disparities that exist in our criminal justice system."

On Monday, Trump, obviously under pressure, said: "Racism is evil. And those who cause violence in its name are criminals and thugs, including the KKK, neo-Nazis, white supremacists and other hate groups that are repugnant to everything we hold dear as Americans."

Then, in a Tuesday Trump Tower press availability, Trump defended his Saturday statement but was hectored by reporters for condemning the "alt-left" demonstrators and allowed himself to be drawn into a needless debate over the merits of Robert E. Lee and whether protesters will soon target George Washington and Thomas Jefferson. Gratuitously and apparently without evidence, he said there were "some very fine people" in both groups.

Like Obama in 2016, Trump this week was (mostly) accurate. But both presidents made themselves vulnerable to the charge of sending dog whistles to favored groups -- playing identity politics. Both failed, to varying degrees and with varied responses, to deliver undiluted denunciations of criminal violence and bigotry.

What's ironic is that the percentages of Americans who support white nationalism or antifa violence are in the low single digits. "Groups like the KKK," reports political scientist Ashley Jardina on a 2016 survey of white Americans, "are deeply unpopular."

But Americans have grown increasingly accustomed to the view that your politics are determined by your racial, ethnic or gender identity. Politics is seen as a zero-sum battle for government favor. College and corporate leaders join in.

Universities sponsor separate orientations, dormitories and commencements for identity groups. (Are separate drinking fountains next?) A corporate CEO fires an employee who has challenged the dogma that only invidious discrimination can explain gender percentages in job categories different from those of the larger population.

America today is a long way from Weimar. But identity politics threatens to get us a little closer. Possible solution: Unequivocally condemn bigotry and violence and, in the fired Google engineer James Damore's words, "treat people as individuals, not as just another member of their group."