Having tried just about every other approach to reforming the Pentagon’s much-reviled system for purchasing weapons, Congress is now moving to embrace the lessons of the marketplace. That’s the implication of news this week that a House-Senate conference reconciling competing versions of the 2016 National Defense Authorization Act will adopt sweeping changes to the defense acquisition system. “Acquisition” is the term bureaucrats use for buying stuff. But judging from the reports the armed services committees in each chamber produced in preparing their defense spending plans for the fiscal year beginning October 1, Congress has had enough of bureaucrats. It is looking for a wholesale change in the culture of the acquisition system.