The secession talk ranges from sardonic social media posts to the heartfelt commitment of organizers who conduct opinion polls and are pushing for independence votes in their own states.

In the run up to almost every presidential election, partisans on both sides of the political spectrum threaten to move to a country like Canada or Ireland if the other side wins. But this election is different.

While popular support for exiting the U.S. remains at minuscule levels even in those states with established secessionist movements, the increased discussion and prominence of the notion is a reflection of the nation’s political polarization. Indeed, by some measures, America is at its most divided since the Civil War.

With the Republican National Convention wrapping up last week in Cleveland and Democrats holding their confab this week in Philadelphia, a recent Pew survey shows that voters hold a more negative view of the opposing party than at any time since polling began in 1992. These feelings have risen to the level of outright fear and anger, often more powerful than the positive feelings voters have about their own party.

“There’s far less trust in the federal government and major institutions than there was 50 or 60 years ago,” says Jason Sorens, author of Secessionism and a lecturer in government at Dartmouth College. “A lot of people don’t feel represented in D.C. and they’re definitely open to radical solutions like secession because they feel as if that’s a way to get control back over their political destiny.”

“While secession movements in the U.S. are minority currents,” adds Sorens, “there’s some evidence they’ve grown slightly in the last few years and they can have an influence on the political conversation even when their objective looks unattainable.”

The states where talk of secession is rising include:

Texas, which was an independent republic before joining the U.S. Texas holds a strong state identity and more conservative ideology than much of the rest of the country. With a higher per capita income than the rest of the nation, Texans can make an economic argument that they’re contributing more to the union than they’re receiving. “The main dampening factor is that Texas has contributed so many presidents that it’s hard to say they’re discriminated against, when they have so much political influence,” Sorens notes.

Vermont’s secessionist movement, the Second Vermont Republic, contributed candidates for governor and state Senate in 2010. The movement was launched when Vermont separated from New York in the 1700s. “The most interesting secessionist movement in the country is Vermont,” says Sanford Levinson, a law and political science professor at the University of Texas, Austin. Levinson notes the state’s history of independence and that one of the movement’s leaders wrote the book Secession: How Vermont and All the Other States Can Save Themselves from the Empire.

Alaska, oil-rich like Texas, has historically contributed more financially to federal coffers than it has received. And it’s the only state that hosts a secessionist movement with its very own political party: the Alaskan Independence Party. In 1990, the party won control of the governor’s mansion but didn’t push for secession from the union.

New Hampshire receives only 70 cents in federal spending for every dollar it sends to D.C. A strong libertarian base is driving the state’s secessionist movement, which is larger than Vermont’s but still small. “There is an economic case for independence because of the fiscal numbers, but there’s not nearly the cultural basis you might have in Vermont or Texas,” Sorens says.

Hawaii boasts a culture distinct from the mainland, which has driven its secession movement in the past. But the state has become more diverse amid rising immigration from Japan. “There’s a little movement in Hawaii,” Sorens says. “Only a small minority of residents has native Hawaiian ethnicity.”

Typically, he says, interest in secession grows in states whose dominant political party opposes the party that controls the White House. So President George W. Bush’s term drove interest in secession in California and Vermont. Under President Barack Obama, Republican-leaning states like Alaska and Texas are more discontented with what they see as federal overreach.

Levinson could envision a win by Donald Trump driving secessionist views in New England, California, or even a unified Pacifica comprised of California, Hawaii, Oregon, and Washington. Likewise, Hillary Clinton taking office would ramp up calls for Texas to become an independent republic again.

It’s important to clarify that a state seceding from the U.S. would be a completely different matter than Great Britain leaving the EU. The EU is a common marketplace, not a single country or political body, and its formation explicitly laid out paths for an exit. The U.S. is a unified country with a constitution that provides no avenue for states leaving.

Many lawyers would say secession is unconstitutional and many laypeople would say that the Civil War settled the question for good. Those in the dissenting camp point out that the U.S. Constitution doesn’t explicitly ban secession, the way that constitutions of countries like France or Spain do.

“If you asked lawyers, is there a legal right to secede, the answer you will get from almost all of them is no. I disagree,” Levinson says. “I don’t think there’s an open and shut legal answer.”

Sorens notes that the 1869 Supreme Court decision in Texas v. White held that a state couldn’t unilaterally leave the union, but it didn’t rule out a negotiated secession. “That decision said states would have to get the consent of the union, the other states,” he says. “It’s unclear how you’d do that.”

Legal questions aside, the question will ultimately be decided politically. “If people en masse really and truly want to secede, legal arguments would be irrelevant. If Texans or Pacificans or Vermonters or New Englanders, if enough of them wake up one morning saying, ‘This system is not conducive to their happiness, we want to get out,’ all the lawyers in the world saying you can’t do that will be irrelevant,” Levinson says. “The first great secessionist movement in American history was what we call the American Revolution.”

For now, it’s clear that there’s insufficient political interest in secession for any of the current movements to succeed any time soon. Even California’s independence movement set a goal of 2020 simply to hold a referendum on secession. You’d need an entire generation to grow up thinking about a state as a separate entity in order for sentiment to shift enough.

But other empires and unions have crumbled many times throughout history.

“I grew up assuming the Soviet Union was simply part of the status quo,” Levinson says. “All of us grew up assuming the United Kingdom was part of the furniture,” when today it seems likely that Scotland and possibly Northern Ireland will leave Great Britain if the UK does exit the EU. “Why do we think the United States of America is etched in stone?”