“there are three trends that we can point to. The first is the steady nationalization of American politics. The second is the sorting of Democrats and Republicans along urban/rural and culturally liberal/culturally conservative lines, and the third is the increasingly narrow margins in national elections.
The combination of these three trends has turned Washington, D.C., into a high-stakes battle where cross-party compromise is difficult, and both sides are increasingly holding out for complete control.
Sixty years ago, state and local politics loomed larger than they do now, which meant national parties operated more like loose labels whose main function was to come together every four years to argue over who should run for president under that party. As President Eisenhower reportedly quipped as late as 1950, “There is not one Republican Party, there are 48 state Republican parties.” The same was true of the Democratic Party at the time. By the 1970s, in fact, many political observers declared that partisan politics had reached their end, with split-ticket voting hitting record-high levels as candidates successfully ran on local issues and pledges to better serve their constituents.
But beneath the surface, the parties were realigning. The civil rights movement of the 1960s and the culture wars of the 1970s and 1980s not only turned conservative Democrats into Republicans and liberal northeastern Republicans into Democrats, it also shifted the focus of politics such that Washington became the arbiter of national values. National parties began building up major fundraising and campaign consultant-driven operations, helping to standardize their messaging so that it actually meant something to vote for a Democrat or a Republican.”
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“Cultural values are much more connected to geography than economic values. Both the rich and poor live in cities, suburbs and exurbs. But those who are socially liberal tend to live in cities, whereas those who are socially conservative tend to inhabit small towns. This partisan sorting on cultural issues has thus generated a significant partisan density divide. And because geography also corresponds to racial and ethnic diversity (basically, cities are multicultural and exurbs are mostly white), this adds another division onto the partisan divide: race.
With all these identities accumulating on top of each other, partisanship has become a kind of “mega-identity,” as political scientist Lilliana Mason argues, with party identification standing for much, much more. In fact, it’s reached the point that when you meet somebody, you can immediately size them up as a “Trump voter” or a “Biden voter.” That kind of easy stereotyping leads us to see the other party as distant and different. And typically, things that are distant and different are also more threatening.”
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“the parties themselves actually have a lot of internal division, which means they share a version of the same dilemma: Republicans and Democrats can’t please all the different voters and groups who fall into their party and want their issue to be prioritized. But in a polarized two-party system, they can make it clear why the other party is bad.”