As Wu points out, this is not a picture of a “heavily polarized” nation, as the pundits would have it. These policies are wildly popular and are outside of the political mainstream because a minority have figured out how to suppress the will of the supermajority.
That small minority of ultra-wealthy people and their well-compensated servants would be nothing but for the fact that they’ve identified the sucker conservative base in 1968 and have in recent decades learned to target and (often through policy decisions) exacerbate their anxieties and delusions in an increasingly fine-grained way (now with the help of hostile and rival state actors).
Progressive Democrats and FDR-style liberals who truly want to break from the party establishment and make the “politically impossible” possible need to start from the proposition that the Know-Nothing 27% of the electorate are write-offs, whose opinions should not be considered or taken into account. That leaves about 70% of Americans to approach with policies emerging from a balance of reality-based populism and informed expert opinion.