WSJ reporter Monica Langley provides a glimpse behind the scenes of how Donald Trump comes up with his attacks on rivals, and statements on immigration, terrorism, refugees. Trump pays close attention to what is riling voters on any particular week, but other rival politicians are not willing to say. He looks for what resonates with the public, and in today's environment where politicians are cautious, careful and plodding, this strategy works. Donald usually puts down a few points on his private plane, looks at reports from campaign staff, yet makes all the decisions himself on what and how to say it. His memory helps, he says. And he has a flair for words, sounding uncouth at times, but yet choosing words carefully enough to sound reasoanble to his audience. In Jan 2016 this approach has worked for Trump in the Iowa and New Hampshire primaries, stalling progress by rival Ted Cruz, and holding back other rivals. Yet this approach has its risks as the primary season progresses. One of the changes in the Republican party politics in 2016 is the emergence of two candidates Donald Trump representing the white working class, and Ted Cruz representing evangelicals, who are both strident and willing to take strong positions on issues in striking contrast to leading Democrats. Trump on China, immigration, refugees, and Cruz on taxes, cultural issues for evangelicals, IRS, Affordable Health Care Act, and both candidates on terrorism. ...