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Former birther Donald Trump has long insinuated that President Obama might secretly be Muslim, having told Fox News in 2011 that Obama "doesn't have a birth certificate. He may have one, but there's something on that, maybe religion, maybe it says he is a Muslim." On Monday Trump again alluded to such conspiracy theories on Fox, slamming Obama for avoiding the use of the term "radical Islamic terrorism" in the wake of the Orlando shooting.

"We're led by a man who is a very — look, we're led by a man that either is, is not tough, not smart, or he's got something else in mind," Trump told Fox & Friends. "And the something else in mind, you know, people can't believe it. People cannot — they cannot believe that President Obama is acting the ways he acts and can't even mention the words radical Islamic terrorism. There's something going on. It's inconceivable."

Trump added that Muslim refugees could be "the all-time Trojan horse," a theory he has used to support his proposed Muslim ban.

"There are a lot of people that think maybe [Obama] doesn't want to get it," Trump added later on NBC. "A lot of people think maybe he doesn't want to know about it. I happen to think he just doesn't know what he's doing. But there are many people that think he doesn't want to get it."