WASHINGTON — Since coming to office in January, Defense Secretary Ash Carter has been given a nearly unprecedented opportunity to remake the entirety of the Joint Chiefs of Staff. But no one service may feel Carter's influence as much as the Army, with both the uniformed and civilian leadership changing over as the service faces fundamental questions of size and mission.

Over the last nine-plus months, Carter has overseen the nominations of Gen. Joseph Dunford as chairman of the Joint Chiefs; Gen. Paul Selva, the head of US Transportation Command, as the vice chairman; Adm. John Richardson, the newest chief of naval operations; Gen. Robert Neller, who was recently confirmed to replace Dunford as Marine Corps commandant; and Gen. Mark Milley, commander of Army Forces Command, who is the newest Army chief of staff.

By next summer, Carter will also have a chance to replace Gen. Mark Welsh as Air Force chief of staff and Gen. Frank Grass as chief of the National Guard Bureau — a clean sweep of the Joint Chiefs.

All the choices bear Carter's fingerprints, said Andrew Hunter, who worked for Carter in a previous Pentagon role.

"To my mind, this is not a random collection of folks," Hunter told Defense News in June. "This looks like what you would expect from Ash Carter — a carefully thought-through group of folks who are not just people he likes, but people he thinks are really going to be able to tackle these jobs they're being assigned to."

That applies doubly for the top leadership positions in the Army, where Carter also has the chance to replace the two civilian leaders for the service. His picks: Eric Fanning, Carter's former chief of staff, as secretary, and Patrick Murphy, a Pennsylvania Democrat who served in the House from 2007 to 2011 and was the first Iraq War vet to be elected to Congress, as undersecretary of the Army.

The choice of Milley as Army chief of staff was considered a surprise pick by Pentagon watchers, with him passing over several more high-profile candidates. But analysts believe Carter liked Milley for his joint experience, as well as the fact the two had worked together previously.

That last point is key when it comes to Fanning.

Fanning is certainly credentialed, having served as deputy undersecretary of the Navy and its deputy chief management officer from 2009-2013 before switching services and joining the Air Force as undersecretary. He also served several months as acting secretary while the confirmation of now-Secretary Deborah Lee James was stuck in Congress.

One of Carter's first moves as secretary of defense was to tab Fanning as his chief of staff, marking the 47-year-old as the head of the secretary's inner circle. In other words, if Fanning gets through confirmation — which should happen, barring someone in the Senate holding him up for political purposes ahead of an election — it would mean one of Carter's closest confidants is now running the Army.

The first order of business for Milley and Fanning both men is to figure out how best to coordinate with each other, said Mackenzie Eaglen of the American Enterprise Institute.

She notes that they have two contrasting styles. Milley is a do-it-all type, who wants to be as involved with every level — a "tornado" of energy. Fanning, in contrast, is an old Washington hand, deft at navigating the politics of the department. Those styles could clash, but if handled correctly, they could provide a powerful team in support of the Army.

"If the two gentlemen don't make a pointed effort from the start to have regular contact that their staffs, make a priority to schedule and keep standing meetings, they'll start strong but fizz fast," Eaglen said. "This town is just a reactive one by nature, and the relationship takes work. But when it's effective, it yields fruit. When it's broken, there are palpable consequences. "

Raymond DuBois, a former acting undersecretary of the Army now with the Center for Strategic and International Studies, said he has talked with both Milley and Fanning about making sure their relationship is strong from the start.

"I have spoken to both of them about the issue and I believe, from what they have told me, that they fully embrace the importance of managing that relationship for the benefit of the institution and our national security," DuBois said.

Fast Challenges

Once that personal stability is in place, the duo will have to contend with an Army that is in flux.

The Army has already cut 80,000 soldiers from its active-duty force, with another 40,000 slated to go by the end of fiscal 2018 for an eventual end-strength of 450,000. Keeping readiness levels high for those soldiers remaining is a priority for the new leadership but also a challenge, given fiscal constraints, whether from a return of sequestration or a long-term continuing resolution.

At the same time the Army is drawing down personnel, the US is being forced to expand its role in Europe and the Middle East as the result of a series of geopolitical crises over the last 18 months. , putting increased pressure on troops and capabilities.

DuBois identifies four key issues the Fanning-Milley team must tackle: maintaining readiness, sorting through the active/reserve force structure mix, deciding how to modernize existing weapon systems for future challenges, and managing the human capital. of the service.

Those are four large challenges, and to tackle them effectively, DuBois said, Milley and Fanning will need to make sure they share the same views on planning.

"It's the planning process that's important," he said. "What they have to do is maintain a very disciplined, focused planning process which ensures that while we may have a smaller Army, it is a ready Army and is not a hollow Army."

And Fanning will need to get going quickly if he wishes to have a lasting impact on the service, because the clock may be ticking.

While Milley is expected to be in his position for the next four years, Fanning's time frame is less certain. If the White House flips to the Republicans, a new president could decide to put his own supporter in as service secretary — potentially introducing another element of chaos for the service.

"Fanning is very professional and competent, but also a committed Democrat," Eaglen noted. "I wouldn't expect him to stay past the time a new person could be confirmed to replace him under a Republican after two terms out of the White House.

"But another Democratic president? You bet they'd keep him around," she added. "They'd be crazy not to with all the churn and turnover and loss of institutional memory that happens during even the calmest of transitions."

However, DuBois says the fact Fanning is coming in at the end of the administration's term will not impact the relationship he has with Milley.

"Make no mistake about it, the military understands what the issue of civilian leadership and control means," he said. "Milley will respond to the secretary of the Army and secretary of defense, and should we have a new one in January of 2017, he will respond to those new bosses."

Email: amehta@defensenews.com

Twitter: @AaronMehta

Aaron Mehta was deputy editor and senior Pentagon correspondent for Defense News, covering policy, strategy and acquisition at the highest levels of the Defense Department and its international partners.

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