Americans mourn the victims of the Aurora, Colo., shooting. In Europe, too, there is grief, mingled with incomprehension. The media chorus: How many more massacres before America adopts European-style gun control?

Christoph Prantner of Austria's Der Standard bemoans American insistence on Second Amendment rights, "even when this freedom occasionally has a very high price and, in a bloody perversion, fatally impairs the freedom of others."

I can't disagree. I just wish Prantner had noted that James Holmes was allegedly wielding Austrian weaponry when he barged into that darkened theater: specifically, a .40-caliber semiautomatic Glock pistol.

For all the tut-tutting across the pond, America's gun culture exists in symbiosis with Europe's culture of precision manufacturing, of which the Glock is a notable expression.

Thirty years ago, Gaston Glock designed this lightweight, rapid-fire killing machine and sold 20,000 to Austria's army. Now his state-supported invention is one of Austria's most successful exports. The tiny alpine nation exported 431,118 handguns to the United States in 2010, according to federal data. Only giant Brazil sold more.

The majority of the Austrian guns were Glocks. And while Glocks have replaced revolvers and U.S.-model pistols in police holsters across the land, most Glock imports are destined for the civilian market, according to journalist Paul M. Barrett, author of Glock: The Rise of America's Gun.

Glock's customers have apparently included not only Holmes, but also Jared Lee Loughner, charged in the 2011 Tucson massacre that left six dead and then-Rep. Gabrielle Giffords among the severely injured, as well as the shooters in the 2007 Virginia Tech massacre (32 murdered) and the 1991 Killeen, Texas, massacre (23 murdered). You might call Glock the favorite weapon of America's Amoklaeufer, as those who run amok with guns are known in German.

But that wouldn't be fair to the makers of the Walther P22 that Virginia Tech shooter Seung Hui Cho also carried, or the Sig Sauer P232 that Steven Kazmierczak bore while killing five people at Northern Illinois University in 2008. Both are German products. With 230,447 handguns exported to the United States in 2010, Germany is the American gun junkie's No. 2 European dealer. All told, European Union members shipped just under a million handguns to the United States in 2010.

Their domestic markets may be limited by gun control, but Europe's arms makers can still get rich thanks to the Second Amendment. Who knew?

The question is what, if anything, to do about the influx of European-made semiautomatic pistols that have transformed the U.S. market — while their manufacturers pay only a modest tariff.

Ordinarily, there's a strong case for free trade: Consumers get the best goods at the best price. But we're talking about a product that can kill people, so I'm not sure the usual considerations apply. Death is a pretty serious "negative externality," as the economists say.

A prohibitive tariff on weapons from Europe wouldn't end U.S. gun violence, but it might reduce risks at the margin. I sort of like the idea of protectionists and gun-control advocates teaming up against the Second Amendment lobby.

Europe's battered economy might suffer, but at least it wouldn't be the first time companies over there gave up U.S. market share so as not to encourage America's evil ways. In December, the European Union restricted sales to the United States of sodium thiopental, an occasionally lifesaving anesthetic. The drug was also being used in lethal injections to carry out the death penalty, which Europe abhors.

As it happens, Holmes could face capital punishment in Colorado, which uses lethal injection. Thank goodness his blood wouldn't be on Europe's hands.

Charles Lane is a member of the Washington Post's editorial board.