Democrats want to take action on gun control in the wake of the mass shooting Sunday in Las Vegas, the deadliest in recent U.S. history. And as the Pew Research Center has found, there is bipartisan support for a number of gun control measures. Yet the chance of the Republican-controlled Congress restricting access to guns in any way seems remote at best — at least in the near term.

Opposition to gun control laws is now a default position of the Republican Party, and guns as an issue has become one of the most polarized topics in modern American politics. More than that, it’s become a defining issue — which party people choose to identify with is inextricably intertwined with their relationship with guns and gun policy. As we wrote in 2012:

Whether someone owns a gun is a more powerful predictor of a person’s political party than her gender, whether she identifies as gay or lesbian, whether she is Hispanic, whether she lives in the South or a number of other demographic characteristics.

Similar to the issue of immigration reform, Republicans are much more conservative on gun control broadly than on individual policy questions. An April 2017 Pew Research Center poll found that 76 percent of Republicans and Republican-leaning independents believe it is more important to protect the rights of Americans to own guns than it is to control gun access. But Pew also found this year that 77 percent of Republicans favored background checks for private sales and at gun shows, and 54 percent favored banning assault-style weapons. It seems, however, that Republicans will vote based on how they feel about the broader issue. Before last year’s presidential election, 90 percent of Republicans said they trusted then-candidate Donald Trump (who was against gun control measures) more than Hillary Clinton on the issue, according to an October Pew survey. That’s very close to the 88 percent of Republicans who voted for Trump, per the exit polls. For comparison, 84 percent of Republicans trusted Trump more than Clinton on immigration.

Among all voters, positions on gun control align nearly perfectly and uniformly with vote choice. In that Pew poll, 48 percent of voters trusted Clinton more on the issue of guns, compared with 47 percent who were in Trump’s camp. That pretty much mirrors the 48 percent to 46 percent margin by which Clinton beat Trump in the national popular vote. The April 2017 Pew poll on whether it’s more important to control gun ownership or to protect Americans’ right to purchase a gun also reflects last year’s election divide nearly perfectly. Slightly more Americans overall favored gun control (51 percent) over protecting gun ownership rights (47 percent).

This gap is reflective of a polarized electorate. Just 22 percent of self-identified Democrats chose protecting gun ownership rights over limiting gun access, compared with the 76 percent of Republicans who did. This 54-point gap is about as wide as you’ll see on any issue. You can see this in the chart below, which shows the difference between how Democrats and Republicans feel on 10 key issues, according to polls taken by the Pew Research Center since 2016.

Only on the question of building a wall along the U.S.-Mexico border was there a wider gap (59 percentage points) between Democrats and Republicans. That’s not too surprising, given that building the wall was a rallying cry for the Trump campaign. But gun rights are even more popular among Republicans. Indeed, it’s pretty astounding to see smaller gaps on supposed culture war issues: The touchstones of abortion and same-sex marriage, while polarized, don’t come particularly close.

That said, the polarization on gun control is a fairly recent phenomenon, so it could change in the long term. As late as 2007, there was just a 27 percentage point gap between the shares of Democrats and Republicans who felt it was more important to protect gun ownership than it was to have tougher gun laws. Over the past 10 years, that gap has widened significantly.

The gap is driven by Republicans who seem to have shifted during President Obama’s two terms in office. Only about half of Republicans were more in favor of gun rights than gun control in 2007, compared with more than three-quarters now.

As a result, it’s hard to imagine congressional Republicans moving on any legislation that limits access to guns. Republicans, led by Trump, are probably going to try to run out the clock on potential gun control legislation as the media moves on from the massacre in Las Vegas. It’s almost assuredly why the White House has said “there will be certainly time for that policy discussion to take place, but that’s not the place that we’re in at this moment.” And with the country split so evenly on gun control, the chance of a Republican being penalized for his or her anti-gun control stance is minimal.

But that’s only true in the short term. As the chart above shows, opinions can shift — even on an issue that seems as intractable as guns. It’s among the most polarized issues now, but it wasn’t always — which means it might not be again.