On Thursday, after Chris Harper Mercer shot and killed 9 people at Umpqua Community College in Roseburg, Oregon, President Obama gave the latest in a tragic series of addresses in response to mass shootings in the U.S. “It cannot be this easy for somebody who wants to inflict harm to get his or her hands on a gun,” he said.

But it is remarkably easy to get your hands on a gun in this country. Of the 11 shootings that prompted Obama to give a public address, eight were committed by gunmen who’d…