In his brief, blunt, and protectionist inaugural speech, President Donald J. Trump declared war on "radical Islamic terrorism," using a phrase that former president Barack Obama refused to say during his eight years in office. Trump vowed not only to defeat the Islamic State and all other like-minded extremist Muslim movements, but to "eradicate" them "completely from the face of the earth." Though Trump paid lip service to the need to "reinforce old alliances," "form new ones," and "unite the civilized world" against extremists to defeat Islamic militancy, the thrust of his main message to America's allies and would-be coalition partners—"America First"—is at odds with that goal.
If America has learned anything from its 15-year struggle against Islamic militancy, it is that such violence and extremism can't be destroyed by force alone, and surely not by one nation's military force. Obama may have been wrong to shy away from calling radical Islamic terror what it is. But he wasn't wrong to assert that America couldn't unilaterally defeat a political movement in religious garb. America needs the coalition of 63 states that Obama and his predecessor assembled to reclaim territory that the Islamic State has seized in Iraq and Syria.
While the U.S. and its coalition allies have retaken more than a third of that territory—which is the size of Belgium—the war against the ideology that attracts so many young, rootless Muslims will be a far longer and tougher battle. Al Qaeda had roughly 2,000 hard-core members when Osama bin Laden attacked America on 9/11. The group, which is now smaller and weaker than the Islamic State, still claims more than 75,000 adherents today.
If anything, the incoming Trump administration will need to be more, not less involved in Islamic militancy's economic, political, and military battle fields. "America First" and "Make America Great Again" may be crowd-pleasing slogans. But they won't help America's European or Arab allies address young Muslim men's attraction to militant Islam, the major causes of which are poverty, joblessness, and political repression in the Islamic world.
An American retreat from concern about the economic and political plight of young male Muslims will be welcomed in Raqaa and Mosul, where the remnants of ISIS still hold sway. Indeed, Islamic militants of all stripes will cheer the isolationist themes that Trump uttered in his inaugural speech.