You know how this debate used to go. When the country was nervous about crime, they preferred a “law and order” candidate like Nixon or Reagan or Bush (see, e.g., Willie Horton) to the bleeding heart running against him. That’s not as true as it used to be, as you can see in the graph below, but if this anxiety keeps trending higher over the next year, it may end up as one of those under-the-radar issues that influences votes far more than, say, Benghazi or Hillary’s private-server natsec disaster does.

Anxiety about crime was sky high in 1992 — the year Democrat Bill Clinton got elected. Anxiety about crime reached its highest level in more than a decade in 2009 — the year Democrat Barack Obama was sworn in. Obviously perceptions that crime is getting worse aren’t an insuperable obstacle for the left in winning a national election. Then again, Clinton ran as a “new Democrat” who’d be tough on crime; in 1994, he signed the Violent Crime Control and Law Enforcement Act, the most sweeping federal crime bill in American history. Thanks partly to that and partly to growing public awareness about falling crime rates, anxiety about crime hasn’t yet returned to its pre-1994 levels. Hillary could, of course, cite Bill’s legacy as evidence that she’d be a law-and-order Democrat too … if not for the fact that she and Bill have spent the last few months trying to please progressives by running away from his crime bill, claiming that it led to far too many people being thrown in federal prisons.

As for Obama’s success in 2009 notwithstanding anxiety about crime, that’s probably a combination of various things. One is simple: After five years of war in Iraq and a financial crash, crime just wasn’t a top priority for most voters. McCain certainly didn’t spend much time on it during the campaign. Another is that anxiety about crime had already risen sharply after 9/11 and remained above 60 percent for most of the rest of Bush’s presidency. If a two-term Republican president hadn’t done much to assuage voter’s fears about it, maybe some voters were willing to gamble on a Democrat. And then, third, it may be that Obama’s election itself produced that 2009 uptick in anxiety about crime because people feared that a liberal (in particular a black liberal, given the racial politics that usually surround this issue) wouldn’t crack down as harshly on an uptick in crime as a white conservative would. If that’s what happened, Obama’s first year in office seemed to reassure some doubters: Anxiety about crime quickly dropped back to Bush-era levels. But now, after a long run in the 60th percentile, it’s back up to 70 again. It’s not so much the hard number there that’s worrisome for Dems, it’s the trend. After a five-year stretch of stability, there’s evidence here that the public thinks the country has regressed. If that feeling grows, what does Hillary do to reassure the worriers — knowing full well that any call for more cops or harsher sentences will run straight into the “Black Lives Matter” movement and its sympathizers?

David Frum wrote about rising crime as a potential political headache for Democrats last month. On the one hand, it’s true that crime, including violent crime, is lower than it’s been in decades. This graph from Gallup shows just how far perceptions about the threat veer away from reality:

Actual crime victims? Droppin’ like a brick. Fears of crime? Steady as she goes. As Frum notes, though, actual crime does appear to be up this year in major cities. FBI director James Comey told reporters at a press conference earlier this month that the spike seems to be a “nationwide phenomenon that’s centered in the cities… Something very, very worrisome is going on.” If that doesn’t change, we’re destined for headlines next year about the long, long downturn in crime rates ominously coming to an end, which is going to spike public anxiety even further. And as Frum argues, that’s going to put Hillary and the Democrats in a bind within their own coalition:

A Democratic party so dependent on black votes is constrained to accept the de-incarceration, de-policing agenda of groups like #BlacksLivesMatter. But that brings us to the second profound political fact: the rejection of the de-incarceration, de-policing agenda by other groups, including other groups that aligned with Barack Obama and the Democrats in 2008.

A 2014 Los Angeles Times survey asked Californians whether local police were too aggressive and posed more of a threat than anything else: 42 percent of black voters said yes, as against 28 percent of Latinos, 21 percent of Asians, and 11 percent of whites. Only 12 percent of whites and 11 percent of Asians could recall a time in the past year when police had treated them unfairly as against 26 percent of blacks. Nationwide, over 80 percent of white millennials believe that crime remains a greater threat than police misconduct.

If crime rates continue to rise through 2016, identification as the “soft-on-crime” or “anti-cop” party may again haunt Democrats as it did a generation ago. Progressives may hope that they can hold together the Obama coalition with an embrace of social welfare, income redistribution, and new issues like universal pre-K. But those policies, too, potentially divide more than they unite.

Could be that this won’t matter any more than it did in 2008/09. If the economy starts growing robustly, Hillary will start pitching herself as a Clinton/Obama economic growth candidate and the GOP is probably cooked regardless of what the crime rate looks like. If the economy slows down, Hillary’s in trouble even if the crime rate dips again. There are, needless to say, various black-swan events that would also scramble the election, starting with a terror attack. But in a close race, especially one where Democrats are counting on high turnout among minorities and the GOP is counting on high turnout among whites — especially blue-collar whites, who stayed home in droves for Romney and who seem to be responding best to Trump in this year’s field — anxiety about crime is a sleeper issue. It’s worth keeping track of how the polls move on this.