Why Paul Ryan's smartest move would be to quit in 2018

Why Paul Ryan's smartest move would be to quit in 2018  CNN Paul Ryan eyeing the exits? Speculation mounts over speaker's future, as source dismisses 'gossip'  Fox News Lawmakers Question How Long Paul Ryan Will Stay in Post After Likely Tax Overhaul  Wall Street Journal Paul Ryan 'soul searching,' possible he could leave Congress after 2018 elections  CNN Paul Ryan Sees His Wild Washington Journey Coming to An End  POLITICO MagazineFull coverage