Bloomberg View has an interesting online debate between economists Tyler Cowen and Noah Smith on "Free Trade and the Populist Backlash."

Bloomberg sets up the debate thusly:

The benefits of free trade have been a cornerstone of economic thought for decades. Recently, though, trade agreements have become the target of a populist backlash, with opposition to trade deals emerging as a key issue in the presidential race. At the same time, new research suggests that trade led to lower wages and higher unemployment for some Americans, particularly middle-class manufacturing workers.

Cowen is much more whole-heartedly in favor of open trade, arguing its benefits far outweigh its costs and have in fact been insufficiently acknowledged:

Given slow middle-class wage growth, it’s a common claim that American politicians oversold the benefits of trade deals to their voters. I take the contrarian view that the benefits of trade deals are more typically underappreciated.

The key point is that America’s longer-term future depends on a world that is relatively free and prosperous.

The last few decades have been the best for mankind in all of history. For the most part, peace has increased, severe poverty has declined and wealth and life expectancy have gone up for most of the world. At such a macro level it is hard to pinpoint the causal role of trade deals in particular, but a relatively free world trading order has been a big part of this process.

Smith favors international trade agreements but with some caveats:

I think economists have done too much one-way cheerleading and not enough thoughtful discussion of the costs versus the benefits.

We know trade can disrupt people’s whole careers and lives. We know it can cause inequality. These aren’t controversial statements in the econ world, and yet economists largely ignored and waved away these issues for decades when talking to the public. Now, as recent research from David Autor and others has shown, we’re paying the price.

Trade with China hurt a lot of U.S. workers in the 2000s — it cut off their careers and shunted them permanently into lower-paying jobs or onto the welfare rolls. If the U.S. had been just a little more restrictive in the amount and the kinds of trade we had allowed with China, maybe we could have protected some of those Americans from getting hurt.

To that last point of Smith's ("If the U.S. had been just a little more restrictive"), Cowen responds:

It’s not always so easy to choose a “little less” free trade…We need such treaties precisely because so many governments have their reasons for wanting a “little less” free trade, and then the final result is a lot less free trade.

You can read the whole thing here. It's a thoughtful discussion on a topic that has been far too politicized – and over-simplified – this election season.