The planned exit of House Speaker John Boehner (R-OH) has upended the political calculus on Capitol Hill concerning the preservation of U.S. defense spending in fiscal year 2016, while Congress is poised to remain mired in partisan gridlock even if a short-term continuing resolution is passed to temporarily stave off a government shutdown. "I am not an optimist at all about what the future holds in a post-Boehner era," said Mackenzie Eaglen, a defense budget analyst at the American Enterprise...