Well if this anti-free trade and isolationist vibe sticks beyond Trump, and the Dems stay moderately pro-business, I could see the Republicans becoming the party of white suburban and rural dwellers, while the Dems become the party of urban dwellers. Where does labor fall into that? I supposed that’s where it might get tricky.
New alignment might look something like:
Dem-- socially left, pro-immigrant, the party of minorities, pro-weed, pro-gay, youth, urban, global-thinking, pro-business, pro-social safety net. Think Millennials who drive Uber, get behind small-business start-ups, global corporations and organizations, new economy and planet-hugging-types, while not being especially religious (at least in the conservative right sense of the word).
Pub- socially right, isolationist, America-first, “traditional” values, rural and suburban, blue collar, pro-gun, anti-regulation, anti-taxation. Think blue collar workers, farmers, largely white, very pro-individual rights, pro worker, adherent to a more-traditional economy and more religious.
It makes it trickier to see where labor would go and business would go. I suppose they could flip allegiances. Or at least be somewhat divided.