Donald Trump has done something politically smart and substantively revolutionary. He is a Republican presidential candidate running against free trade and, effectively, free markets.
By putting trade at the top of the conversation he elevates the issue on which Hillary Clinton is the most squirrelly, where her position reinforces the message that she will say anything to get power.
But mostly it's politically smart because Donald Trump's only shot at winning the presidency is to smash and replace the entire structure of the American political debate. For the past 80 years that debate has been about the size of government — Republicans for less government and more market, and Democrats for more government and less market.
If that debate structures this election, Trump will get somewhere between 38 percent and 44 percent of the votes — where he's been polling all year.
Trump's only hope is to change the debate from size of government to open/closed. His only hope is to cast his opponents as the right-left establishment that supports open borders, free trade, cosmopolitan culture and global intervention. He would stand as a right-left populist who supports closed borders, trade barriers, local and nationalistic culture and an America First foreign policy.
In an age of anxiety, that closed posture might have a shot at winning. On trade, for example, 60 percent of Republicans, 49 percent of Democrats and 50 percent of independents believe that trade agreements are mostly harmful, according to a Brookings Institution/Public Religion Research Institute study.
I personally doubt that Trump will be able to pull off a right-left populist coalition. His views on women and minorities are unacceptable to nearly everybody on the left. There's no evidence that he's winning over many Sanders voters or downscale progressives.
But where Trump fails, somebody else will succeed. And that's where he's substantively revolutionary. The old size-of-government question was growing increasingly archaic and obsolete. In country after country the main battle lines of debate are evolving toward the open/closed framework.
If you don't like our current political polarization, wait 10 years. One way or another it will go away. When the frame of debate shifts to open/closed, sometime soon, the old coalitions will smash apart and new ones will form. Politics will be unrecognizable.
It's significant that Trump gave his big anti-trade speech in the Pittsburgh area. That part of Western Pennsylvania illustrates in a very concrete way how the open/closed debate will play out.
Pittsburgh is a great renaissance story. I recently got a tour of it from the mayor, Bill Peduto. We visited a beautiful, tight Italian community with family-owned businesses stretching back generations. We visited a resurging African-American community where local activists were building a cultural center in the home of the great playwright August Wilson. Mostly we just saw acres and acres of new development: new restaurants, new museums, new loft-style office spaces and several gleaming new hospitals.
Pittsburgh has come so far from the deindustrialization days of the 1970s and 1980s.
But then I drove through the steel mill towns along the Monongahela and other rivers. The storefronts and banks were boarded up, the downtowns deserted. The mills are still operating but they are so efficient that they're eerily empty of human presence. The towns still have residents but not much is going on. I drove for miles, unable to find even a diner for lunch.
It occurred to me the Pittsburgh renaissance didn't really grow up out of the metro Pittsburgh of old. Instead, one Carnegie-Mellon-type layer of prosperity and innovation had grown on top of the old working-class layer, which was still there and in bad shape.
When you're in the top layer you see why free trade is so good. Living standards are rising. A study by the Peterson Institute found that past trade liberalization laws meant between $7,100 and $12,900 in additional income to the average household. A study by Peter Petri and Michael Plummer estimates that the Trans-Pacific Partnership, which Trump opposes and Clinton sort of opposes, would boost American incomes by $131 billion.
You also see how an efficient manufacturing sector makes it possible to divert resources into things that improve the quality of life. As Neil Irwin pointed out in The New York Times, Pittsburgh has lost 5,100 steel jobs since 1990. But it has also gained 66,000 health care jobs over the same time.
The problem is getting people from the bottom layer to the top layer — a 30-minute drive but a universe away.
The prophets of closedness will argue that the problem is trade. The prophets of openness will argue that we need the dynamism that free trade brings. We just need to be more aggressive in equipping people to thrive in that dynamic landscape. If facts still matter in this debate — and I'm not sure they do — the proponents of openness are massively right.
David Brooks is a columnist for the New York Times.