Jonathan Chait of The New Republic suggests that Jim Manzi wasn’t comparing apples to apples in his National Affairs essay. Jim responds directly, and convincingly, here, but I have some additional thoughts.

First, we’re dealing with counterfactuals and ideas that are difficult to soundbite. The real mystery, as I suggested below, is why Europe didn’t grow much faster than it did relative to the U.S., which, by virtue of being the economic leader, should have experienced slower productivity growth than economies that were simply applying its lessons to their own economies — applying high savings rates to implementing techniques that had proven successful in a competitive environment.

I’d go further. The United States had a number of handicaps relative to Europe over this period, including the burden of very high defense expenditures and a tax system that focuses on income rather than consumption, unlike the more efficient (and more regressive) tax systems that predominate in Europe. Also, our educational system — not exactly the most neoliberal feature of the U.S. economy — failed miserably to yield the productivity gains we saw across other domains of the economy. Our human capital advantage, which was enormous for most of the 20th century, eroded and eventually vanished.

Moreover, the U.S. did a far better job of creating an inclusive labor market, which absorbed workers from throughout the developing world but particularly from neighboring Mexico, where more-skilled individuals tended to stay in-country or migrate to large cities while large numbers of less-skilled migrated to the U.S. There are costs and benefits to this strategy, and it may be productivity-enhancing due to the match between increased work effort among more-skilled Americans and the use of less-skilled to outsource household labor, e.g., child care, preparation of meals, etc. But it could also have proven a drag on productivity per worker hour.

Given these challenges, why did the U.S. experience relatively robust productivity growth? One argument — which I believe — is that we unleashed the entrepreneurial energy of Americans in such a way that we overcame these challenges. Had we also pursued aggressive education reform and tax reform and entitlement reform, and if the USSR decided to go under a decade early or Europe decided to bear a fair share of the defense burden, it seems plausible that the U.S. productivity growth edge would have been even higher.

To me, the evidence in favor of open, entrepreneurial economies is extremely strong and shouldn’t be a partisan issue. U.S. Republicans haven’t pursued the policies we need to strengthen ours, some European social democrats have pursued policies to strengthen theirs. It’s depressing to watch this debate become a partisan squabble. The thing about Jim’s essay is that he didn’t frame it as a celebration of Republican policies. Rather, it was a thoughtful take on the upsides and downsides of social democracy, and why the United States needs a more balanced growth model. The hyperpartisanship of some critics blinds them to the central insights of the essay.