Mike Blake / Reuters

During the Democratic primary debate at the Felt Forum in New York City, in April 1988, Al Gore pointed out that Michael Dukakis had a big problem.

The senator from Tennessee mentioned that the Massachusetts governor, who had leapt to the front of the Democratic primary field, had sustained a furlough program that involved “weekend passes for convicted criminals,” one of whom had committed rape and assault while furloughed.

I thought of that moment in the Democratic debate in 1988 last week, after former Obama Housing and Urban Development Secretary Julián Castro was pilloried for suggesting that former Vice President Joe Biden, the front-runner for the nomination, was struggling to recall the details of his own health plan, asking Biden, “Are you forgetting what you said just two minutes ago?” Some Democrats, including the Biden campaign, suggested Castro had taken a “cheap shot;” Representative Vicente Gonzalez even switched his endorsement from Castro to Biden. Castro, for his part, said that his remarks were “not a personal attack.”

Let’s say it was a cheap shot. Let’s say it was personal. So what?

Back in 1988, Gore, languishing in third place behind Dukakis and Jesse Jackson, was trashed as a sore loser. His mention of the furlough program was rude. It was shocking. It was uncivil. Maybe even racist. Gore “had, it seemed, engaged in the clumsiest kind of negative campaigning, and countenanced a harsh and racially charged strategy to advance his own improbable candidacy,” The New York Times recalled in a 2000 retrospective. During the debate, Dukakis, comfortable in his front-runner status, breezily dismissed Gore’s criticism. “Al, the difference between you and me is that I have to run a criminal-justice system,” Dukakis replied. “You never have.” The Massachusetts governor would go on to cite low crime statistics in his home state.

Dukakis led George H. W. Bush handily in polls well into the summer, but Bush’s focus on crime, and Republicans’ emphasis on one of the inmates who had been furloughed, Willie Horton, helped turn his campaign around. (Some political scientists have argued persuasively that the original Horton ad was less significant than remembered, and that an expanding economy in 1988 was more of a factor in the Dukakis rout than Bush’s successful exploitation of racialized fears around crime.)

Lee Atwater, Bush’s campaign manager, was delighted by the Willie Horton line of attack. He crowed that he had recently seen Jackson in Dukakis’s driveway, and that if Dukakis was contemplating Jackson as a running mate, then he might “put this Willie Horton on the ticket after all is said and done.” (The source of the intended humor in Atwater’s joke was that Horton and Jackson are both black.)

The Horton ad, produced by a PAC, stated that “Dukakis not only opposes the death penalty, he allowed first-degree murderers to have weekend passes from prison,” and ended with the tagline, “Weekend prison passes, Dukakis on crime.” During a presidential debate, the CNN moderator Bernard Shaw asked Dukakis, “Governor, if Kitty Dukakis were raped and murdered, would you favor an irrevocable death penalty for the killer?” Atwater himself might as well have been moderating.

As it happens, not many people appear to have seen the original Horton ad. Rather, most Americans who became aware of it in 1988 probably saw references to it in media coverage, which amplified its message far beyond the original ad purchase. The current occupant of the White House is tremendously good at getting the press to amplify racist messaging, even if they are attempting to condemn or debunk it.

Nevertheless, the lesson the Democratic Party took from Dukakis’s loss to Bush was that it could not afford to be “soft on crime.” The next Democratic nominee, Bill Clinton, presided over the execution of a mentally disabled black man, Ricky Ray Rector, in the middle of the primary, as if to show that unlike Dukakis, he would not shy away from extreme measures in the name of public safety. Rector had killed a police officer, Bob Martin, and then turned his weapon on himself, removing a large chunk of his own brain—his attorneys described him as functionally a “zombie,” and not mentally competent to understand what he was being punished for. Nevertheless, Clinton would be as tough on crime as he needed to be to assuage the fears of white voters, no matter the cost—he would not make the same mistake as the previous Democratic nominee.

Republicans loved crushing Dukakis in the 1988 election, but many were less than pleased that Willie Horton became a shorthand for racist campaigning. In the years since, they have attempted to saddle Gore with the responsibility for the Horton attack, even though Gore did not mention Horton by name in the debate, and did not run a national campaign centered on Horton. The contradictory premises of the Republican counterargument, that the Horton ad was not racist but that Gore was responsible for the racist Horton ad, should be familiar to anyone living through the Trump era. The Bush campaign, the Republican Party, and their enablers in the conservative media bear the full responsibility for one of the most racist campaign ads of the latter half of the 20th century, just as Democrats bear full responsibility for responding by attempting to out-tough the GOP on crime.

Nevertheless, in raising the furlough program, Gore had identified an obvious weakness for Republicans to exploit—one Dukakis was ill-prepared to address once the general-election campaign began, in part because Gore was so immediately and completely dismissed. If the issue had been taken seriously, Dukakis might instead have been forced to develop a compelling response—and had he been unable to do so, Democratic primary voters could have cast their ballots with that in mind. Dukakis would later tell New York magazine that he wrongly believed that “the country was tired of the kind of polarization we’d had under Reagan,” and that deciding that he “was not going to respond to the attacks” was “the biggest mistake of my political career.” The advice he wished he had gotten, he added, was that “you’ve got to be ready for the attacks, and you’ve got to have a carefully thought-up strategy to deal with them.”

The 2020 campaign promises to be one of the dirtiest in history. The incumbent president is an alleged felon clinging to an extra-constitutional grant of presidential immunity. He is relentlessly dishonest, even when it is flagrantly obvious he is lying. He has attacked his opponents’ families and their appearances; he even attempted to frame a rival’s father for the assassination of President John F. Kennedy which, while mildly amusing in its absurdity, illustrates the absence of limits on what Trump is willing to say. Donald Trump has refused to countenance any constitutional limits on his authority, and will almost certainly turn the power of the federal government toward weakening whichever opponent emerges from the Democratic primary. But among his most reliable and frequently deployed tools is his use of racism and prejudice to frighten and divide the American people.

The Democratic nominee, to have even a ghost of a chance, not only must survive a gauntlet of baseless smears and a sycophantic propaganda machine the envy of North Korea; he or she will have to be able to neutralize the president’s appeals to Americans’ worst political impulses. Biden owes his front-runner status in no small part to the perception among his own voters that he is a more moderate, comforting figure to white voters who may have cast ballots for Barack Obama in the past, but who sided with Trump in 2016. Biden, for his part, has tried to cast himself as an old-school tough guy who would have “beat the hell out of Trump” if they were in high school.

If that’s the case, then Biden should be able to take a mean jab or 20 about his age or mental faculties. Because there is no question that whatever Biden would get from Trump as the nominee would be cheaper, dirtier, and nastier than anything his Democratic opponents will offer. And if he can’t take that, then Democrats looking for the best candidate to take on Trump should probably look elsewhere. You can argue that Biden is the toughest candidate in the race, or that he’s old and it’s mean to pick on him, but you can’t do both.

As unpleasant as it might be, Democrats who shy away from exploiting their rivals’ weaknesses are not doing their party a favor: They are preventing primary voters from determining which of them has the strength to sustain whatever Trump, the Republican Party, and Fox News are going to throw at them—and what the mainstream press will amplify in pursuit of ratings and false balance.

That last thing Democrats should be doing, if they want to win the next presidential election, is nominating a candidate who can’t handle an opponent being unfair.

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