The reason lies with the incentives that U.S. military aid creates.

Limitless and beyond the view of the public, U.S. military aid is a tap foreign governments don’t want to turn off. The longer they’re “fighting terrorists,” the more “security assistance” they get. There’s no reason for them to actually defeat terrorists, because if they did, the cash would go away. Instead, foreign security partners are incentivized to maintain a form everlasting instability, wherein nobody wins and everybody loses.

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After 15 years of letting the military take the lead in fighting terrorism, policymakers need to accept that political problems demand political and diplomatic solutions, which are seldom found on the path of least resistance. But the tools needed — robust diplomacy, accountability mechanisms, democracy support — are starved of funding.

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By relying on military aid, the United States is fostering a world of endless war and insecurity. For the United States’ so-called security partners, that’s good for business.

By Funding Foreign Militaries, the U.S. Is Spreading Terrorism
http://fpif.org/funding-foreign-militaries-u-s-spreading-terrorism/