Sending a dog whistle to the GOP’s anti-Obama base, Donald Trump has taken to saying that “there’s something we don’t know about” the president when it comes to issues like terrorism and the resettlement of Syrian refugees.

While Trump has never come out and said what that he thinks that “something” is, the GOP presidential frontrunner told conservative radio host Michael Savage yesterday that he believes Obama may actually be a terrorist sympathizer.

“It’s radical Islamic terrorism,” Trump said. “We have a president that won’t even use the words and if you don’t use the words, you’re never going to get rid of the problem. We have a — maybe he doesn’t want to get rid of the problem. I don’t know exactly what’s going on.”