The outcome of dueling versions of the National Defense Authorization Act could determine how much the U.S. lines Russia's pockets before what some lawmakers hope is a speedy transition to a domestically produced rocket engine. The RD-180 engine is built by NPO Energomash, a manufacturer mostly owned by the Russian Federation. It's used in the Atlas V rocket, built by Lockheed Martin and Boeing's United Launch Alliance. The House version of the NDAA approves all of the 18 requested engines. In the Senate, where there has been a lengthy battle over buying from Russia, the NDAA authorizes nine engines. Either...