Rereading Teixeira and Abramowitz today, one is struck by their eerie prescience, but also by the fundamental difficulty of holding together a Democratic Party where highly educated and affluent adults are the ascending faction but are not numerous enough to carry an election by themselves. This past year, that difficulty has come into sharp focus as the pandemic has set the educated class that leads the party on a collision course with its traditional union base.

That crash might have come sooner if private-sector unions hadn’t been largely a spent force. If White manufacturing workers and manual laborers had remained the party’s “prototypical” voters, as Teixeira and Abramowitz say they were in the mid-20th century, one can imagine that shift of the highly cosmopolitan “mass upper middle” toward Democrats might have stalled over issues such as immigration and trade.

These days, however, “labor” is more likely to mean government unions, which account for a slight majority of all unionized workers. Public-sector unions aren’t worried that the local school system is going to outsource its teaching to China or that courthouse jobs will be taken over by immigrants from Guatemala. So the party could keep singing the same hymns to organized labor even as the congregation turned over and its theology changed.

Progressive professionals might not like every single thing the teachers unions or the transit workers did, but they could live with it — and if services became really intolerably bad, they moved someplace where the unions were less intransigent, even while insisting that they were very supportive of public services, and of a well-paid government workforce represented by government unions.

The death of George Floyd, however, made it a little bit harder to voice full-throated support for government unions. Progressives raged at each new revelation of how insulated police officers had been from any sort of accountability for abusing their power. They had a whole bevy of union-negotiated special protections that made it hard to convict bad cops, and just as hard to separate them from the force.