A group of think-tank analysts gathered Tuesday to discuss a series of hypothetical budgets they constructed in an attempt to address long-term Pentagon spending challenges. The analysts and teams composed of colleagues each built 10-year budgets using a "strategic choices" tool developed by the Center for Strategic and Budgetary Assessments. On opposite ends of the ideological spectrum were Tom Donnelly of the American Enterprise Institute, who built a budget that exceeded the fiscal year 2017 defense spending plan by $1.3...