To my friends supporting Donald Trump: The Trump coalition is broad and complicated, but I believe many Trump fans are well-meaning. I have spoken at length with many of you, both inside and outside Nebraska. You are rightly worried about our national direction. You ache about a crony-capitalist leadership class that is not urgent about tackling our crises. You are right to be angry. I'm as frustrated and saddened as you are about what's happening to our country. But I cannot support Donald Trump. Please understand: I'm not an establishment Republican, and I will never support Hillary Clinton. I'm a...