Twelve years ago this month, a little-known Illinois state senator named Barack Obama brought a Democratic convention to its feet with these words :  

“There’s not a liberal America and a conservative America; there’s the United States of America. There’s not a black America and white America and Latino America and Asian America; there’s the United States of America.”  

Sadly, these divisions have only widened as fissures have become chasms and clefts now resemble the abyss. If only it were possible to build lasting bridges between blue America and red America. If only the election of a black president (twice) had marked the final chapter of the tragic American narrative that began with slavery.  

If only. The saddest words in the English language.  

A month that began with tears in Baton Rouge, St. Paul and Dallas is slated to end with the nomination of the least popular presidential candidates in more than two decades. A cartoon by John Darkow in the Columbia Daily Tribune shows the rival campaign headquarters with these slogans: “SHE’S NOT TRUMP” and “HE’S NOT HILLARY.”  

This is a campaign year in which it is easy to get caught up in false equivalency. Hillary Clinton’s use of home-brew email servers was risky, foolish and self-indulgent . But Donald Trump’s entire candidacy is risky, foolish and self-indulgent.  

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GOP Lobbyist Backs ‘Free the Delegates’ After Butting Heads With Trump

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Trump’s latest swerve — auditioning a dismissed general as his general election running mate — is just the latest indication that the would-be GOP nominee has problems understanding the norms of democracy. Trump’s favorite military man, retired Lt. Gen. Michael Flynn, enraged social conservatives by coming out in favor of abortion rights in a Sunday interview on ABC’s “This Week.”  

Unlike Dwight Eisenhower (who served as NATO Supreme Commander and president of Columbia University after World War II), Flynn radiates contempt for civilian authority. Describing his firing as the director of Defense Intelligence Agency in 2014, Flynn wrote in the New York Post over the weekend, “Here we are in the middle of a war … and here it was, the bureaucracy was letting me go.”
Flynn then added a word — undoubtedly milder than the ones he used at the time — “Amazing.”  

Just after I wrote the above paragraphs on Flynn, the mercurial Trump reversed field yet again. In a Monday interview with the Washington Post’s Chris Cillizza , the bilious billionaire confided, “I have five people, including the general. I do like the military, but I do very much like the political.”  

By apparently delaying his vice-presidential pick until the weekend before delegates gather in Cleveland, Trump runs the risk of losing control of his own convention. Trump may not fully grasp that the delegates are free agents when it comes to nominating a VP — and they have the power to reject his choice.  

In 1972, the hapless George McGovern was forced to deliver his acceptance speech at 3:00 am (in an era before TV taping) because the vice-presidential roll call vote descended into chaos. Seventy different candidates — real and imaginary — received VP votes including Yippie Jerry Rubin and TV’s Archie Bunker.  

Even worse, McGovern’s pick, Tom Eagleton , soon had to drop out when it was revealed that he had received electroshock treatments.  

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Sanders to Campaign With Clinton in New Hampshire

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This year’s Democratic convention, in contrast, promises to offer all the excitement of non-stop synchronized swimming coverage from the Rio Olympics. With Bernie Sanders slated to endorse Hillary Clinton in New Hampshire on Tuesday and with the Bernie Brigades satisfied with such platform promises as a $15 minimum wage, the Philadelphia coronation looks like it will be mild in the streets and on the convention floor.  

But the fall campaign promises to be noxious — maybe even uglier than in 1988, when George H.W. Bush trafficked in racial fears by highlighting the case of Willie Horton, a convicted murderer who killed again while out on a prison furlough program supported by Mike Dukakis.  

As president, though, Bush transcended the campaign that elected him. Unlike his son, the first Bush’s war against Saddam Hussein was authorized by the United Nations and did not include regime change. The 41st president’s political folly stemmed not from ideological extremism but rather from abandoning his no-new-taxes pledge to staunch the deficit.  

Ever since Jimmy Carter talked about “the moral equivalent of war” to bring Americans together in common purpose, presidents have dreamed of national unity in peacetime. George W. Bush claimed in the 2000 campaign to be “a uniter, not a divider.” And Monday, Donald Trump declared — reading off a TelePrompTer — “We’re going to become, for the first time in a long time, a united country.”  

Amid Trump’s long history of lies, fabrications and ludicrous statements, it is hard to top the absurdity that he would be the leader who brings America together. This from a candidate who began his race for the White House by reveling as protesters were beaten up at his rallies. This from a candidate who admires authoritarian leaders who quash dissent like Vladimir Putin.  

Trump’s promise of unity — in the same speech that he embraced the Nixonian code words of “law and order” — reminds us of the burden that fate has handed Hillary Clinton.  

Out of the wreckage of a terrible year, she is the only American, if elected, who might build a bridge across the 21st Century. May she somehow campaign as if she were worthy of the task.  

— Roll Call columnist Walter Shapiro is a veteran of Politics Daily, USA Today, Time, Newsweek and the Washington Post. His book on his con-man great-uncle was just published: “Hustling Hitler: The Jewish Vaudevillian Who Fooled the Fuhrer.” Follow him on Twitter @MrWalterShapiro.