“It is just a complete muddlement, if you will,” Corker said on CNN. “And I don't know the president just seems to be very uncomfortable being commander-in-chief of this nation.”

Corker gave Obama credit for attending a GOP Senate lunch hours before his address. In an interpersonal setting, Corker said Obama has been impressive on the issue. But he has not translated that to the public, Corker said. 

“He just cannot follow through,” he said. “He cannot speak to the nation as a commander-in-chief. He cannot speak to the world as a commander-in-chief. He just cannot do it. And I don't know what it is.”

In the past, President Obama has been criticized for just the opposite — giving lofty speeches but failing to work with Congress. 

As one of the few Senate Republicans to sign off on the authorization of military force pushed by Obama, Corker acknowledged the gravity of his words. But he said Obama’s speech Tuesday night left him heated. 

“I probably shouldn't be saying everything I am saying right now,” he said. “But I guess it was a result of last night. My temperature level is up slightly today.”

President Obama in his speech Tuesday said U.S. national security as well as U.S. principles are on the line in making his case for military action in Syria.

But Obama said he will also pursue a peaceful solution to securing Syria’s chemical weapons after it and Russia have shown a new willingness to comply with demands.