Pentagon officials are bracing themselves for increased friction between the Defense Department and the White House with John Bolton’s pending arrival as President TrumpDonald TrumpOhio Republican who voted to impeach Trump says he won't seek reelection Youngkin breaks with Trump on whether Democrats will cheat in the Virginia governor's race Trump endorses challenger in Michigan AG race MORE’s national security adviser.
Bolton, who Trump selected to replace H.R. McMaster earlier this month, enters a Cabinet already rocked by the February ousting of Secretary of State Rex TillersonRex Wayne TillersonThe Hill's Morning Report - Presented by AT&T - Supreme Court lets Texas abortion law stand Trump-era ban on travel to North Korea extended Want to evaluate Donald Trump's judgment? Listen to Donald Trump MORE, who differed with the president but was seen as having a good relationship with Defense Secretary James MattisJames Norman Mattis20 years after 9/11, we've logged successes but the fight continues Defense & National Security — The mental scars of Afghanistan House panel advances 8B defense bill MORE.
Mattis, who met Bolton for the first time this week, publicly stressed that he had “no reservations, no concerns at all,” in working with the hawkish former George W. Bush administration official.
“Last time I checked he’s an American. I can work with an American, OK? I’m not in the least bit concerned with that sort of thing,” Mattis said prior to the meeting.
And within the Pentagon, some were encouraged by the first exchange between Bolton and Mattis.
When Mattis received Bolton on the steps of the Pentagon on Thursday, he joked that he heard Bolton was “the devil incarnate.”
“Thank you for coming. It's good to finally meet you. I heard you’re actually the devil incarnate, and I wanted to meet you,” Mattis said, as captured by reporters' microphones.
“I take that as a good sign that Mattis thinks he can work with him,” a source familiar with the situation at the Pentagon said.
At the same time, this source said there is skepticism that Mattis and Bolton will make for a great team.
“I don’t think they will get along,” the source said. “I think they’ll be at odds.”
White House chief of staff John KellyJohn Francis KellyMORE has sought to build a team that is ordered and disciplined, and there are some at the Pentagon who think Bolton — seen as a bomb-thrower when it comes to internal administration politics based on his years in the Bush administration — will not be on the same page.
“If he tears that down, it’s not going to function well,” the source said of Bolton.
Bolton will enter his new role on April 9 with views directly opposite to those of Mattis.
Bolton has on numerous occasions called for pre-emptive strikes on North Korea — most recently arguing the case in a Wall Street Journal op-ed in February — while Mattis has routinely stressed diplomacy.
And while Bolton has frequently advocated for regime change in Libya and Syria, the Pentagon has sought to avoid such a conflict.
The opposing views are likely to cause problems, according to retired Army Lt. Col. Daniel Davis, who served under McMaster while in the service.
Officials within the Pentagon are “afraid that [Bolton’s] going to make the president lean more towards the military options in ways that the military don’t support. There are stakes set, I think, for some conflict there,” who now works for the Defense Priorities Foundation, a think tank created by associates of billionaire businessman and donor Charles Koch.
Mattis also shares no prior relationship with Bolton, unlike McMaster, an Army lieutenant general who shared a common background with the retired four-star Marine Corps general.
“McMaster and Mattis didn’t always see eye to eye, but they are both military men,” the source said.
“They understand it’s not always necessary that they see eye to eye, it’s necessary though that they don’t throw bombs at one another through the president.”
Bolton, who served as U.S. ambassador to the United Nations under the Bush administration, and as undersecretary of State in the years leading up to the Iraq War, does have “some extraordinary skills in working within government and working the bureaucracy,” Davis said.
But he also comes with a “significant deficiency ... he has no personal understanding of how strategic ideas [will impact] decisions on the ground,” Davis added.
When talking about using military force on North Korea, for example, “I don’t think he has a very good understanding of what it really means on the ground and how it so badly could impact our own interests, whereas Mattis is on record as really emphasizing what it would cost,” he said.
Mattis in the past has warned North Korea in stark terms that it faces devastation if it does not end its pursuit of nuclear weapons, but he also tempers that stance with warnings that any conflict would be “tragic on an unbelievable scale.”
“Our effort is to work with the [United Nations], work with China, work with Japan, work with South Korea to try to find a way out of this situation,” Mattis said last May.
Bolton, meanwhile, has argued that the “only diplomatic option left is to end the regime in North Korea.”
“Anybody who thinks more diplomacy with North Korea, more sanctions ... is just giving North Korea more time to increase its nuclear arsenal,” he said on Fox News in September.
A regular on Trump-favorite Fox News and conservative talk radio, Bolton may also play into the president's bolder tendencies, such as last year’s Twitter warning of “fire and fury” in Pyongyang.
“It’s one thing to be on a TV program and say some bold things, but it’s another thing to be in the job and have a sense of authority,” the source told The Hill. “His views may cause some dissent.”
“The real question is going to be, who is Trump going to listen to more?” Davis said. “Mattis is doing his job and going wherever, whereas Bolton is always going to have his ear, and sometimes the last guy in your ear is the one you remember.”
But Mattis as Cabinet secretary does have more authority.
“I can not see Mattis just succumbing to Bolton, giving in to him or having him run roughshod over him. He is the secretary of Defense and he does have the direct authority whereas Bolton doesn’t. It’s possible you can have some conflict there. That’s certainly what I’m going to be watching for.”
This story was updated on April 2 at 6:03 p.m.