Defense Secretary Jim Mattis and President Donald Trump at the Army-Navy football game in Philadelphia, Saturday, Dec. 8, 2018.

Defense Secretary Jim Mattis and President Donald Trump at the Army-Navy football game in Philadelphia, Saturday, Dec. 8, 2018. (Susan Walsh/P)

WASHINGTON – With the impending departure of Defense Secretary Jim Mattis, a battle could be brewing on who should replace him with President Donald Trump pitted against Capitol Hill lawmakers, who must confirm the Pentagon’s next top official, experts said Friday.

Mattis’ resignation letter Thursday made clear that he and Trump did not agree on the president’s abrupt announcements to drawdown troops in Syria and Afghanistan.

The next defense secretary will have to be in lockstep with Trump’s foreign policy and offer a new level of loyalty at the Pentagon that could be subject to the political whims of the commander in chief, experts said.

“He will need somebody who is actually aligned with the president’s view of a non-interventionist,” said retired Lt. Col. Daniel L. Davis, a senior fellow and military expert for Defense Priorities, a right-leaning Washington think tank. “Trump has to have somebody who is on his team. So anybody who’s got the interventionist credentials probably shouldn’t apply.”

Mattis now leaves behind a gaping hole in military leadership that could set Capitol Hill and Trump on a collision course. Senate Republicans and Democrats, who must confirm Mattis’ successor through hearings and a floor vote, have already been vocal that they want another Mattis to succeed him.

But Trump could desire someone who is more of a loyalist.

Davis suggested someone like former Virginia Democratic Sen. Jim Webb, a former Navy secretary who worked in former President Ronald Reagan’s administration, could meet those requirements. And if Senate lawmakers are in agreement, Mattis’ successor could be in place by as early as February.

Either way, the decision on who replaces Mattis could be fraught with conflict and controversy in light of the way that the Pentagon chief resigned, essentially rebuking the president for his increasingly unilateral approach to foreign policy.

Paul Rieckhoff, the founder and CEO of Iraq and Afghanistan Veterans of America, said Mattis had served as a stabilizing hand during a tumultuous two years and his departure leaves the military and veterans communities in a “fragile” state.

“If you look at the cumulative situation, our military and veterans need stability and Mattis has been this block on everything from the parade to the transgender ban to Syria to Afghanistan,” Rieckhoff told CNN’s John Berman on Friday.

Rieckhoff issued a warning for the precarious road ahead.

“This is a very concerning fragile moment in American history especially for our military and veterans community,” Rieckhoff added.

Mark Cancian, a senior adviser with the Washington think tank Center for Strategic and International Studies, said it’s unclear who could win over the Senate and Trump.

He said he believes someone like Webb might be too much of an independent. And sitting senators who have been suggested in the past, such as Sens. Tom Cotton, R-Ark., and Lindsey Graham, R-S.C., might not be the right picks at this time.

Trump has been burned already several times by picking Republican lawmakers who’s seats were later lost to Democrats. More so, Graham has expressed outrage at the president’s plans to remove troops in Syria and Afghanistan.

“The conventional names may not resonate particularly because those people would espouse the same policy positions that caused Mattis to resign,” Cancian said. “It could be somebody who is quite different and closer to the Trump perspective. It may be an unusual name from the business community.”

Cancian said the next candidate for defense secretary could be someone like Secretary of State Mike Pompeo or an existing Pentagon leader.

Michael O’Hanlon, a senior fellow and director of research for the foreign policy program at the liberal leaning Brookings Institution, said the Trump nominee also could be a close ally such as former House Speaker Newt Gingrich or former New York City Mayor Rudy Giuliani. Defense Deputy Secretary Pat Shanahan also could be considered.

Trump’s sudden decisions to drawdown troops in Syria and Afghanistan that sparked Mattis’ resignation marked for perhaps the first time in American history the departure of a defense secretary in protest and adds to the overall unease that remains, experts said.

“I think it adds to a feeling that in some sense the wheels are beginning to come off of American foreign policy and national security policy,” said John Hannah, a senior counselor at the Foundation for Defense of Democracies, a nonprofit, nonpartisan research institute on foreign policy and national security in Washington.

Hannah said he thinks the Mattis resignation will inevitably affect troop morale because he was an advocate for servicemembers.

James Carafano, a vice president at the Heritage Foundation, a conservative think tank in Washington, said the next secretary of defense should be as prestigious as Mattis but needs to navigate Capitol Hill better.

“We have two years, we’re going to have a lot of defense debates, we’re going to have a big nuclear modernization debate,” he said.

For Carafano, two such people who have an understanding of defense policy and the legislature are outgoing Sen. Jon Kyl, R-Ariz., and former Republican senator Jim Talent from Missouri, he said.

“Neither of whom probably want the job, but I think they’d be great,” Carafano said.

Stars and Stripes reporter Dianna Cahn contributed to this report Twitter: @cgrisales Twitter: @caitlinmkenney

Sign Up for Daily Headlines

Sign up to receive a daily email of today's top military news stories from Stars and Stripes and top news outlets from around the world.

Sign Up Now