Conservative pundit Bill Kristol told MSNBC's "Morning Joe" that the retirement of Defense Secretary James Mattis sends a "chilling" message about the decision-making process inside the White House.
The retired U.S. Marine Corps general sent a strong rebuke of President Donald Trump and his foreign policy in his letter announcing his decision to leave the administration, and Kristol said the departure was a big deal.
"It so dwarfs everything else that's happening right now," Kristol said.
Kristol said the Mattis retirement came as a surprise to the military and the secretary's own friends, even after Trump made the unexpected decision to remove U.S. troops from Syria.
"I spoke with a retired general just a couple days ago who is close to Mattis and discreet about his conversations with Mattis, but has been in touch with Mattis throughout," Kristol said. "He said he's going to hang in there, Jim really thinks it's important for the country. Jim doesn't have a big ego, but he thinks he's there, he think he's doing good. He will take a lot of blows and hang in there to prevent worse things from happening."
Kristol said his decision to retire shows that he no longer believes he can do good inside the White House.
"For me the resignation is so important because it's not simply that he's disgusted about the Syria decision or disappointed by it, though he is, or even appalled by it," he said. "This means that Mattis thought he could not stop a lot of other bad decisions from happening down the road."
"Mattis saw what was coming and thought, 'I can't make a difference anymore,'" Kristol added. "He has swallowed an awful lot, he has put up with an awful lot. He's told people he's going to stay for four years, he told friends of mine that as recently as this month. The fact that Mattis felt he couldn't do any good anymore, which is what I think that letter suggests, really, for me, is a chilling moment. The fact that he felt he couldn't stay and do any good is even worse."