A group of senior Pentagon officials who play key roles in deciding which weapon systems the U.S. military develops and buys began an 11-day trip this week to meet with senior commanders around the world, holding discussions designed to ensure the Defense Department is buying the right equipment for tomorrow's force. Vice Adm. Evan Chanik, the Joint Staff director of force structure, resources and assessment (J-8), is leading the Oct. 10 to Oct. 21 expedition -- informally known as a...