Libya’s Moammar Gadhafi spent decade piling up a huge stash of weapons like a crazy old lady hoarding cats. Ironically, rebel forces looted his arms depots to turn Gadhafi’s missiles and guns on their old master. But the ease with which the rebels were able to arm themselves points to their next massive problem: securing those weapons before they fuel a lethal insurgency or flood the global arms bazaar.

It’s a concern familiar to those who watched Iraq’s insurgency evolve. Saddam Hussein, like Gadhafi, amassed a vast array of conventional weaponry for defense against enemies both foreign and do...