WASHINGTON — Army Chief of Staff Gen. Mark Milley said he supports additional troops in Afghanistan and keeping a residual force in Iraq should Mosul be retaken from the Islamic State during a Senate Appropriations defense subcommittee hearing Wednesday.

Now, one week past a bombing in Kabul that left 150 people dead, Sen. Lindsey Graham, R-S.C., asked the chief, looking toward the next decade, if he would support an increase in troop presence in Afghanistan as an interim solution.

Milley said he would support an increase but would not offer specific numbers as they are currently under analysis as part of Defense Secretary Jim Mattis' major strategic readiness review.

Graham also asked Milley if he believed the U.S. should leave a residual force in Iraq should Mosul be taken from the Islamic State. The chief said he would make such a recommendation if Iraq's government would consider it.

Milley was less forthcoming as to whether more troops are needed in South Korea as North Korea grows increasingly cantankerous and active in its missile testing.

"That is a very difficult question full of all kinds of nuances. I can't give you a yes or a no," Milley said, adding, the situation in Korea calls for a forward presence with the right capacity to respond to a belligerent North Korea, but that may not mean more troops.

The bottom line: the Army will likely continue to play a growing role in stabilizing hot spots around the world. And recent history has taught that drawing down or pulling out troops from war-torn countries before the government is stabilized leaves a vacuum for the resurgence of terrorist organizations to gain footholds and power, making it more likely U.S. forces will stick around unstable regions in the future.

And Graham noted the kind of force projection necessary to suppress conflict could be dangerously hampered should sequestration remain in effect.

Milley said roughly 50 percent of the demand from combatant commands and 70 percent of unexpected urgent demand are met by Army forces. He added there are roughly 180,000 soldiers deployed in 140 countries conducting training, deterring opponents, conducting humanitarian assistance, participating in peacekeeping missions and supporting combat operations.

The Army's fiscal year 2018 budget request funds for the total Army, to include active, National Guard and Reserve, at 1,018,000 troops.

The service’s unfunded requirements list in 2018, sent to the Hill last week, shows the Army would want to grow the force beyond the status quo, seeking $3.1 billion to add 10,000 troops for the active force, 4,000 for the Army National Guard and 3,000 for the Army Reserve.

The wish list — known formally as an unfunded requirements list — is typically sent to Congress by each of the services to help guide Capitol Hill in considering additional funding beyond the budget request Congress might provide as lawmakers begin to draft the policy and spending bills.

Milley told lawmakers Wednesday that the current active Army end-strength at 476,000 was not adequate to maintain troops ready to respond to contingencies around the world.

He said he believed the right size for the Army now would be around 540,000 to 550,000 troops in the active force, 353,000 to 355,000 for the Guard and 205,000 to 209,000 for the reserve.

Yet, more clarity on the right size of the force across the U.S. military services will come from Mattis’ strategic readiness review. The review is due out later this summer, according to defense officials.

Jen Judson is an award-winning journalist covering land warfare for Defense News. She has also worked for Politico and Inside Defense. She holds a Master of Science degree in journalism from Boston University and a Bachelor of Arts degree from Kenyon College.

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