Behind Mitt Romney’s Increasingly Lonely Challenge to Donald Trump

Mitt Romney’s advisers begged him not to go to war with...Trump. After he decided to go ahead, Mr. Trump dismissed him as “lightweight” and “failed candidate.” This week, Newt Gingrich called him “pathetic.” Mr. Romney, sticking to his guns, has become a rare figure in American history—a former presidential nominee openly defying the man succeeding him as his party’s standard-bearer. Sitting at his home on the Pacific Ocean last week, Mr. Romney reflected on the waves he created by attacking Mr. Trump, how his family helped persuade him it was the right thing to do, and how he increasingly finds...