With ISIS continuing to fight, Russia and China throwing their weight around, and budget shortfalls becoming bigger and bigger problems, the Department of Defense will definitely need strong leadership in the form of a commander-in-chief and his political appointees in the months immediately following the inauguration next year.
Here are 7 important decisions he or she will have to tackle:
1. Will the U.S. pressure China to get off of contested islands, force them off with war, or let China have its way?
America has a vested interest in navigational freedoms in the South China Sea. Many allies transport their oil, other energy supplies, and manufactured goods through the South China Sea and the U.S. Navy uses routes there to get between the Pacific and Indian oceans.
Currently, a few sets of islands in the area are contested, most importantly the Spratly Islands. In addition to controlling important sea routes, the area may hold vast supplies of oil and natural gas. The most optimistic estimates put it second to only Saudi Arabia in terms of total oil reserves
China is deep in a campaign to control the South China Sea by claiming historical precedent and by building new bases and infrastructure on them. An international tribunal ruling on the issue will likely side against China shortly, but China probably won't accept the decision.
That leaves a big decision for the next president. Does America recognize Chinese claims, back up U.S. allies in the area through diplomatic pressure, or begin a military confrontation that could trigger a major war?
2. How dedicated is the U.S. to the NATO alliance and deterring Russian aggression?
For decades, America's presence in NATO was unquestionable. Candidates might argue about specific NATO policies, but membership was a given. Now, a debate exists about whether NATO might need to be adjusted or a new, anti-terror coalition built in its place.
America pays more than its fair share for the alliance. Every member is supposed to spend 2 percent or more of its GDP on defense, but only America and four other countries did so in 2015. Even among the five who hit their spending goals, America outspends everyone else both in terms of GDP and real expenses. The U.S. is responsible for about 75 percent of NATO spending.
And NATO was designed to defeat Russia expansion. Though members assisted in the wars in Iraq and Afghanistan, they've struggled with what the alliance's responsibilities are when addressing ISIS. For those who think ISIS should be the top priority, there's a question about why the U.S. is spending so much time and energy on a European alliance.
So the question before the next president is, should America continue to dedicate diplomatic and military resources to a Europe-focused alliance when ISIS continues to inspire attacks in America and Europe while threatening governments in the Middle East?
3. What part of the world is the real priority?
To use the cliche, "If everything is a priority, nothing is." The American military does not have the necessary size and resources to contain both Russia and China while fighting ISIS and other terrorist organizations. The next U.S. president will have to decide what is and isn't most important.
Alliances can help the U.S. overcome some of the shortfalls, but each "priority" requires sacrifices somewhere else. The next president will have to decide if protecting Ukranian sovereignty is worth the damage to negotiations in Syria. They'll have to decide if the best use of military equipment is to park it in eastern Europe to deter Rusia or to send it to exercises in Asia to deter China.
Obama spent most of his administration trying to pivot to Asia while Middle Eastern and European crises kept forcing America back into those regions. Where the next president decides to focus will decide whether Russia is contained, China is pushed off the manmade islands, and/or if ISIS and its affiliates are smothered.
4. What is America's role in the ongoing fight against ISIS and is there a need for more ground troops?
On the note of transferring forces, those vehicles that could be redirected from supporting NATO or conducting exercises could be set to Iraq, Syria, and other countries to fight ISIS, but is that America's job?
Though America's invasion destabilized the region, Iraq's rulers asked U.S. troops to leave before putting up a half-hearted and strategically insufficient response to ISIS. So the next president will have to decide whether America owes a moral debt to prop up the Iraqi government and Syrian rebels and whether it is in America's best interest to do so.
The answer to those two questions will fuel the biggest one, should America deploy additional ground forces (something generals are asking for), risking becoming mired in another long war, to stop the rise of ISIS and other terrorist groups in the region?
5. How long will the Air Force keep the A-10?
The struggle between A-10 supporters and detractors continues to rage. Air Force officials and A-10 detractors say the plane has to be retired due to budget constraints and the limited ability to use the plane in a contested environment. Proponents of the A-10 insist that it's the cheapest and most effective close-air support platform.
The battle has nearly come to a head a few times. The Air Force was forced by Congress to keep the A-10 flying and finally agreed to a showdown between the A-10 and F-35 for some time in 2016. The critical analysis of the results will almost certainly come while Obama is still in office, but the A-10 decision will likely wait until the next president takes office.
The decision will officially be made by the Air Force, but the president can appoint senior officers sympathetic to one camp or the other. Also, the president's role as the head of their political party will give them some control when Congress decides which platforms to dedicate money to supporting.
So the new president will have to decide in 2017 what close air support looks like for the next few years. Will it be the low, slow, cheap, and effective A-10 beloved by ground troops? Or the fast-flying, expensive, but technologically advanced and survivable F-35?
6. How much is readiness worth and where does the money come from?
Sequestration, the mandatory reduction of military and domestic budgets under the Budget Control Act of 2011, puts a cap on U.S. military spending. The service chiefs sound the alarm bell every year that mandatory budget cuts hurt readiness and force the branches into limbo every year.
The next president, along with the next Congress, will have to decide how much military readiness they want to buy and where the money comes from. To increase the percentage of the force that is deployed or ready to deploy at any one time without sacrificing new weapons and technology programs, money would need to be raised by cutting other parts of the federal budget or raising taxes.
So, what size conflict should the military always be ready for? And where does the money for training, equipment, and logistics come from to keep that force ready?
7. How many generals and admirals should the U.S. have?
As the number of U.S. troops has decreased in the past 30 years, the number of U.S. general officers has rarely dropped and was actually raised by over 100 since Sep. 11, 2001, causing a 65 percent increase in the number of four-star officers to total number of service members. This has led to questions about whether it's time to ax some generals and admirals.
Former Secretaries of Defense Chuck Hagel and Robert Gates both proposed serious cuts, and the Senate Armed Services Committee has recently floated a 25 percent reduction in the total number of general officers.
Not only would this significantly cut personnel costs since each general and their staff costs over an estimated $1 million per year, but it would reduce the bureaucracy that field commanders have to go through when getting decisions and requests approved.