Chris Matthews has long championed the​ Republicans-are-all-just-a-bunch-of-birthers argument​. And on his Thursday program he resurrected it again, this time using Donald Trump and his invite to speak at CPAC to insinuate the conference and the conservative movement is promoting the idea Obama is an “illegal immigrant.”

Matthews hosted Al Cardenas, head of of the American Conservative Union (which puts on CPAC), and former RNC chair Michael Steele and cornered them on Trump.

Why more time for the number one birther in the country?” Matthews asked, referring to Trump getting more speaking time than others such as Wisconsin Governor Scott Walker. That was after playing several old clips of Trump asking to see Obama’s birth certificate.

“He is nutty on the issue of birtherism,” Matthews emphasized. “I mean, that’s what he’s known for now. Not building towers into the sky.”

And that’s when Steele stepped in to offer a defense.

“I think that characterization can be put behind Donald Trump,” Steele said.

“He won’t put it behind him,” Matthews quickly retorted.

“Oh, Chris, he hasn’t been talking about that–,” Steele tried to respond before Matthews interrupted with disagreement.

After some back and forth, Steele finally got agitated: “Chris, nobody’s talking about it but you! You did a 30-second lead in on it.”

“You know why? Because people who think the president is an illegal immigrant shouldn’t be talking out loud almost anywhere,” Matthews responded. “They think he’s an illegal immigrant. That he snuck into the country, broke our laws, and is a fraud.”

“All that’s now behind us,” Steele responded.

Later, Matthews asked Cardenas if he would be happier if Trump didn’t talk about the birther issue, to which Cardenas offered a simple, “Yes.”

Watch the fireworks below (which also includes Matthews going after Allen West):

(H/T: Mediaite)