There’s been a big to-do in the econoblogsphere over an essay by James Manzi in National Affairs; unfortunately for Manzi, it hasn’t been the kind of debate you want. Manzi asserts that having a European-style social democracy is terrible for growth:

From 1980 through today, America’s share of global output has been constant at about 21%. Europe’s share, meanwhile, has been collapsing in the face of global competition — going from a little less than 40% of global production in the 1970s to about 25% today. Opting for social democracy instead of innovative capitalism, Europe has ceded this share to China (predominantly), India, and the rest of the developing world.

Manzi’s numbers were picked up widely, including by the Times’s own Ross Douthat.

But as Jonathan Chait quickly pointed out, Manzi’s definition of Europe included the Soviet bloc (!), so that he was attributing to social democracy an economic decline that was mainly about the collapse of communism. Chait also suggested that Manzi wasn’t comparing the same dates for America and Europe; and most importantly, Chait pointed out that to the extent there has been a growth divergence, it’s almost entirely because America has faster population growth; since 1980, real GDP per capita in Western Europe and the US have grown at almost the same rate.

But I went back to Manzi’s source of data, and it turns out that it’s even worse than that. If you use the broad definition of Europe, which includes the USSR, it did indeed have 40 percent of world output in the early 1970s. But that share has not fallen to 25 percent — it’s still above 30 percent.

The only thing I can think is that Manzi compared Europe including the eastern bloc in 1970 with Europe not including the east today.

It’s probably not a deliberate case of data falsification. Instead, like so many conservatives, Manzi just knew that Europe is an economic disaster, glanced at some numbers, thought he saw his assumptions confirmed, and never checked.

And that’s the real moral of the story: the image of Europe the economic failure is so ingrained on the right that it’s never questioned, even though the facts beg to differ.