The Washington PostDemocracy Dies in Darkness

Our Donald Trump-inspired tribalism, in 3 remarkable charts

If there is one issue on which President Trump has upset the political apple cart, it's free trade. Republicans were once the party of globalization. Suddenly, not so much.

And perhaps no issue has illustrated as clearly that our political polarization doesn't owe so much to principled beliefs about the free market and the size of government, but rather to tribalism and the powerful personalities of our leaders.

Witness this new chart from an NBC News/Wall Street Journal poll, which shows unprecedented polarization on free trade. Not only have Republicans cooled to the idea as Trump has spent months deriding trade deals; over that same span, Democrats have apparently had an even bigger epiphany about their own feelings on free trade. They're now very much for it! Wonder what caused that?

(Never mind that their base demanded that both Bernie Sanders and Hillary Clinton oppose President Obama's Trans-Pacific Partnership (TPP) free-trade deal just last year.)

According to the poll, 57 percent of Democrats now say free trade is generally a good thing, compared with 27 percent in 2010.

Pew's polling also has shown increasing polarization on free trade over the past seven years. But unlike the NBC/WSJ poll, it has shown mostly on the Republican side of the ledger. While in 2009, just 31 percent of Republicans said free trade was a bad thing, that was up to 61 percent in an August poll.

(Given that this poll is a few months old, it's possible that it has missed another bump in support for free trade among Democrats.)

And lastly, new polling from Gallup shows that one specific free-trade deal — the North American Free Trade Agreement (NAFTA) — is becoming increasingly polarizing. While the two parties were split on it in the late 1990s and early 2000s, it's now approved by 67 percent of Democrats and just 22 percent (!) of Republicans.

When NAFTA passed, it bears noting, it had the support of more than 75 percent of Republicans in both the House and the Senate. Now, only about a quarter of Republican voters say it's a good thing.

Three polls, three yawning gaps on free trade that didn't really exist before the 2016 campaign.

Perhaps Trump has persuaded Republicans to do some real soul-searching on this issue, and they've decided they're no longer pro-free trade. And perhaps Democrats truly have come to realize that opposing things like TPP — which, again, was just last year — isn't really what they are all about.

Or maybe there are a whole lot of Americans who have decided they're for whatever Trump is for, and a whole lot of other Americans who have decided they're against whatever he's against.

Enjoy the next four years.