Back when everybody was assuming that Donald Trump was a one-month wonder at most, there wasn’t much reason to worry about the trouble his kind of heresy might cause Republicans beyond the immigration demagoguery that lifted him into contention. But now it may be time to look forward a bit more, as Greg Sargent did today in thinking about Trump’s likely crusade against the Trans-Pacific Partnership:

[A]nother very ripe opportunity for Trump to make his GOP rivals even more miserable may be lurking right around the corner, and it could expose the same sort of schism between GOP elites and GOP voters that Trump’s forays into immigration policy have.

I’m talking about the massive global trade deal called the Trans-Pacific Partnership. Some time in the next six months — in late 2015 or in early 2016 — the participating nations may finally reach a deal on the TPP. That may well come just when the GOP primaries are heating up.

Virtually all of the major GOP presidential candidates, including Jeb Bush, Scott Walker, and Marco Rubio, all support the TPP, as do Republican Congressional leaders.

Not Trump, or for that matter, Mike Huckabee or Ted Cruz (who conspicuously flip-flopped on the trade deal this summer)….

The TPP seems like the perfect opening for Trump to turn up the volume on his particular strain of right wing populism, which includes harmonies such as the promise of protectionism for American workers to “make America great” at a time when they are threatened by immigrants, China, and shadowy global elites. With other GOP candidates backing the TPP, this could provide another test of whether GOP voter opinion really is aligned with GOP elite opinion, this time on free trade.

And that will be a very interesting test.

I used to be a trade wonk a long time ago, and I can tell you that public opinion on this set of issues is volatile and malleable–in both parties. There are certain kinds of Republicans (management types), and people in certain industries (agriculture) and regions (the Pacific Coast) who tend to be “pro-trade” in a general sort of way; it’s also true of younger people. But that leaves a lot of older Rust Belt and southern conservatives who don’t much like anything that’s “international” unless it involves blowing things up. And where it exists, the support for trade tends to be a bit superficial. I had a member of Congress tell me during the 1990s that “I’m for exports; it’s just those imports I don’t like,” with zero awareness you cannot have the former without the latter.

So yeah, this will be interesting, and on top of everything else, there’s a certain Democratic presidential candidate whose position on TPP could well be forced into the open by a Trump crusade.

Ed Kilgore

Ed Kilgore is a political columnist for New York and managing editor at the Democratic Strategist website. He was a contributing writer at the Washington Monthly from January 2012 until November 2015, and was the principal contributor to the Political Animal blog.