Threats from violent extremism increasingly undermine security and development around the globe. From Afghanistan to Nigeria, terrorists seek to expand their reach and resonance by exploiting ongoing conflicts and insurgency, joining forces with criminal networks, establishing safe havens in weak and repressive states, and propagating hatred via social media. Even as we work to defeat and degrade the most virulent terrorist group—Da’esh—and restrain the wanton murder, slavery, and violence it spreads, we know that its defeat on the battlefield is not enough.