The person pointed to the times Ryan has felt the need to publicly rebuke Trump in the last several months. There was Trump’s temporary Muslim ban proposal; his refusal in one interview to disavow David Duke and the Ku Klux Klan; and Trump’s acceptance, or even encouragement, of violence at his campaign rallies. Those were the things that disturbed Ryan enough for him to speak out at the time, and those are the things that trouble Ryan enough to withhold support of Trump now.
“We’re talking about identity politics — that’s what he was referencing,” said the person familiar with Ryan’s thinking. “Identity politics is what Paul was getting at. He spoke out against the Muslim ban, against allowing a culture of violence at some of these campaign events, against the Duke comments. He’s just saying our party deserves a leader who is committed to unifying, not dividing, our party and our country. We’ve always said we would disagree on policy.”