The private sector has all the tools we need to flag rapid weapons build-ups and suspicious purchases. All that's needed is the political will to build the most basic database.
Big data might have stopped the massacres in Newtown, Aurora, and Oak Creek. But it didn't, because there is no national database of gun owners, and no national record-keeping of firearm and ammunition purchases. Most states don't even require a license to buy or keep a gun.
That's a tragedy, because combining simple math and the power of crowds could give us the tools we need to red flag potential killers even without new restrictions on the guns anyone can buy. Privacy advocates may hate the idea, but an open national database of ammunition and gun purchases may be what America needs if we're ever going to get our mass shooting problem under control.
Just look at the gun-acquiring backgrounds of some of our more recent mass killers to see what I mean. James Holmes, the Aurora shooting suspect, went to three different locations spread out over 30 miles to legally buy his four weapons. All three were reputable outdoors retail chain stores. He then went online, and bought thousands of rounds of ammunition along with assault gear. UPS delivered around 90 packages to Holmes at his medical campus in that short period. It doesn't take a PhD in statistics to see that a quick, massive buildup of arms like this by a private individual -- especially one, like Holmes, who was known in his community for having growing mental health issues -- should raise a red flag.