Not long ago, the idea of another American Civil War seemed outlandish.

These days, the notion has not only gone mainstream, it seems to suddenly be everywhere.

Business Insider published a poll in October 2020 saying a majority of Americans believed the U.S. was already in the midst of a "cold" civil war. Then last fall, the University of Virginia Center for Politics released a poll finding that a majority of people who had voted to reelect former President Donald Trump in 2020 now wanted their state to secede from the Union.

The UVA data also showed a stunning 41% of those who voted for Joe Biden in 2020 also said it might now be "time to split the country."

Researchers have found such downbeat assessments of America's democracy are especially salient among the young. Last month, the Institute of Politics at Harvard's Kennedy School published a poll that found half of voting age Americans under 30 thought our democracy was "in trouble" or "failing." A third also said they expected there to be "a civil war" within their lifetimes. And a quarter thought at least one state would secede.

The more one hears this particular drumbeat, the louder it becomes.

Late last year, the University of Maryland and The Washington Post produced a poll saying that one-third of Americans thought violence against the government was "sometimes justified" — a belief they found even more widely held among Republicans and independents. According to the Post, just about 1 American in 10 held that view in the 1990s.

Do the respondents in all these polls fully realize what these terms mean or their answers imply? Possibly not. Talk is often cheap, and pollsters can ask a lot of provocative questions in pursuit of something noteworthy — or buzzworthy.

What do people even mean by "civil war"? Let us assume it would not be a return to the 1860s, when 11 Southern states left the Union and fought a four-year war to assert their right to do so and preserve the practice of slavery, which had about 4 million African Americans in bondage at the time.

The American Civil War cost the lives of at least 600,000 Americans and contributed to the deaths of many thousands more. It devastated the South economically and left most of those in the region who had been emancipated to lives of peonage and penury.

Moreover, it did little to settle the constitutional issue of "states' rights," a problematic point in our national conversation ever since. Salient in the struggles for civil rights and voting rights, it remains so in the squabbles over the mask and vaccine mandates of today.

States' rights, still with us

The rights of states to go their own way on fundamental issues are also still front and center in the Supreme Court, where abortion rights pose an immediate example. Texas and other states want to make the procedure all but unavailable, while much of the nation prefers the access granted nationwide by the court's Roe v. Wade decision in 1973.

"We already are seeing 'border war' with individual states passing major legislation that differs considerably from that in other places," says Darrell West, director of governance studies at the Brookings Institution, and William Gale, a Brookings senior fellow in economic studies, who have written a pair of articles on the fraying of the American social and political fabric.

They note that conflicts between entire states are not the only way civil war may emerge in our time, or even the most likely. When and if the issue turns to violent confrontations between local citizens and federal officers, or between contentious groups of citizens, the clash might well take place far closer to home. As West and Gale write:

Today's toxic atmosphere makes it difficult to negotiate on important issues, which makes people angry with the federal government and has helped create a winner-take-all approach to politics. When the stakes are so high, people are willing to consider extraordinary means to achieve their objectives.

And what do these careful scholars mean by "extraordinary means"?

"America has an extraordinary number of guns and private militias," they write. How many? They cite the National Shooting Sports Foundation's estimate of 434 million firearms in civilian possession in the U.S. right now. That would be 1.3 guns per person.

"Semi-automatic weapons comprise around 19.8 million in total," they add ominously, "making for a highly armed population with potentially dangerous capabilities."

The New York Times recently reviewed How Civil Wars Start by political scientist Barbara F. Walter of the University of California at San Diego. In an interview with NPR member station KPBS in San Diego a year ago, Walter said the Jan. 6 attack on the Capitol was surprising but should not have been because we had been watching "American democracy decline since 2016."

A scholar of international law, Walter adds: "The U.S. used to be considered a full democracy like Norway, Switzerland or Iceland," she said, "and it's now considered a partial democracy like Ecuador, Somalia or Haiti."

Drawing different lines today

The geographical divides in our time are different from those of the 1860s. We can still trace the original Mason-Dixon line that separated the regions of "free soil" from "slave states," and there are real differences on either side of that ancient demarcation even today.

But the most meaningful geographic separation in our society is no longer as tidy as North and South, or East and West. It is the familiar divide between urban and rural, or to update that a bit: metro versus non-metro.

Thus a "blue state" such as Maine has populous coastal counties that voted for Biden and sparsely populated interior counties that went heavily for Trump, enough to tip the majority to him in one of the state's two congressional districts. Conversely, in ruby red state Nebraska, one congressional district anchored in the city of Omaha went for Biden.

This dynamic also shows up in the biggest population states, the top prizes in the Electoral College. In California, where the coastal cities are famously liberal, the Central Valley counties are still far more conservative.

And in Texas, Biden carried the six largest metros in 2020, due largely to their growing numbers of people of color. But most of the state's 254 counties are outside these metros; in rural Texas, the Republican vote share is still the lion's share.

That may change over time, but for now we're less a nation divided into 50 states than we are two nations that are both present in each of those states. Each is dominant in its own space and certain that it is the real America.

You can measure some of this geographic/demographic division in the 2020 election results. Trump won in 2,588 counties covering most of the national landscape, as Republican candidates usually do. (This is why we are accustomed to Election Night maps that are strikingly red even as the popular vote is close or leans Democratic.)

Biden, in stark contrast, carried only 551 counties, less than a quarter as many as Trump. But the counties Biden carried had a total population of nearly 198 million, while Trump's altogether had just 130.3 million. That is a difference of nearly 68 million people. Put another way, Biden won the counties that are home to 60% of the total U.S. population.

It is hard to believe when staring at a map on which Biden's counties are scattered blue dots on a sea of red. But those blue dots are where most of the country lives. When you look at the top ten states by metro percentage of total state population, Biden won all ten.

Trump did win a few inner-core urban counties here and there, with a combined population of 4.7 million. Biden won the rest of that category with a combined population of 97 million. That is a ratio of 20 to 1.

Moreover, the Biden counties are where most of the population growth is happening. Less than a fifth of the counties account for 77% of the Latino or Hispanic community and 86% of Asian American community nationwide.

Is civil war a self-fulfilling anxiety?

The forces of disunity are disquieting, to say the least. But must it all come to blows? Can we still center ourselves and pull back from whatever brink we are approaching?

Irish Times writer Fintan O'Toole offered a cautionary message just before Christmas in The Atlantic, recounting some of his horrific memories from "the troubles" in his homeland in the late 1900s. Even then, he says, with all the provocation on both sides, "it never got to a full-blown civil war."

It doesn't do to behave as if our divisions must compel us to bloodshed, he adds, because dwelling on such thoughts and making such predictions may bring that prospect closer to reality, even if intended to do the opposite.

That makes sense, especially if you believe that too much thinking about the unthinkable can become acceptance of the unacceptable.

And however you personally regard the meaning of what happened on Jan. 6, 2021, we know now that nothing in American politics is unthinkable.

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