Security experts often disagree when ranking America’s security challenges, but most believe that the top three are violent Islamic extremism, Russia and China. These adversaries or potential adversaries have radically different capabilities and goals, but share one characteristic: All seem to be beating the United States on what can be called “the battlefield of perception.”

Unconstrained by democracy and driven by a fierce pursuit of power, they adroitly craft and disseminate narratives to weaken and delegitimize the existing international order and undercut American will, thus seeking to counterbalance the U.S. advantage in military and economic power. They consider belief and perception as much a part of war as any physical fight. “We are in a battle,” al-Qaida leader Ayman al-Zawahiri explained, “and more than half of this battle is taking place in the battlefield of the media.” The “war of the narratives has become even more important than the war of navies, napalm, and knives,” added Omar Hammami, a leader of Somalia’s al-Shabab terrorist movement. ...