Today there are more Islamist terrorists around the world than there were on September 11, 2001. John Hannah argues that this statistic alone speaks to the failure of American efforts to wage a war of ideas alongside that on the battlefield. To do so effectively, he argues, Washington must exert pressure on those countries that have sowed the ideas that have given rise to al-Qaeda and Islamic State—including Iran, Turkey, and Qatar, but also friendlier nations:

One important example concerns what President Trump discussed in Riyadh back in 2017: the need for America’s Muslim partners to take the lead in defeating the ideology of Islamist extremism. Or more importantly, the need for a handful of states, first and foremost Saudi Arabia, to get out of the business of exporting supremacist versions of the faith around the world. Yet you’d be hard-pressed to find Trump ever speaking publicly about the issue again. Instead, his demands on the Saudis rapidly shifted to shorter-term, more transactional issues like buying ever-greater quantities of U.S. weapons, keeping oil prices low, and supporting what in all likelihood will be a stillborn plan for Middle East peace. . . .

That’s particularly unfortunate, because the Saudi crown prince Mohammad bin Salman has himself claimed since late 2017 that Riyadh is now determined to destroy the extremist ideology that it did so much, for so long, to promote. To the crown prince’s credit, it hasn’t all been lip service. [For instance, the Saudi-based] Muslim World League’s . . . head, Mohammad al-Issa, a cleric and former justice minister, has made a series of remarkable statements in what appears to be a sincere one-man campaign to promote moderation—including condemning Holocaust denial, promising to visit Auschwitz, and telling Muslim minority communities to “embrace the nations they live in,” strictly obey national laws, and positively integrate into society. . . .

But Wahhabism’s trail of wreckage runs deep and wide. It will take much more than a few op-eds by a single Saudi cleric to make a dent in the damage that’s been done.

Last month, two potent reminders were on vivid display. In the run-up to Indonesia’s national elections, several reports detailed the troubling expansion of Saudi-backed Wahhabism in the world’s most populous Muslim-majority country. . . . And in the aftermath of the Easter attacks in Sri Lanka, article after article described the inroads that Wahhabism had made over decades, generating serious fractures within Sri Lanka’s Muslim community and establishing a fertile breeding ground for the kind of violent extremists who perpetrated the bombings.

Earlier this month, an operative working for, or in conjunction with, Hizballah snuck across the Israel-Lebanese border and planted a sophisticated explosive near the town of Megiddo, which killed a civilian when detonated. On Thursday, another Iranian proxy group launched a drone at a U.S. military base in Syria, killing a contractor and wounding five American soldiers. The former attack appears to be an attempt to change what Israeli officials and analysts call the “rules of the game”: the mutually understood redlines that keep the Jewish state and Hizballah from going to war. Nadav Pollak explains how he believes Jerusalem should respond:

Israel cannot stop at pointing fingers and issuing harsh statements. The Megiddo attack might have caused much more damage given the additional explosives and other weapons the terrorist was carrying; even the lone device detonated at Megiddo could have easily been used to destroy a larger target such as a bus. Moreover, Hizballah’s apparent effort to test (or shift) Jerusalem’s redlines on a dangerous frontier needs to be answered. If [the terrorist group’s leader Hassan] Nasrallah has misjudged Israel, then it is incumbent on Jerusalem to make this clear.

Unfortunately, the days of keeping the north quiet at any cost have passed, especially if Hizballah no longer believes Israel is willing to respond forcefully. The last time the organization perceived Israel to be weak was in 2006, and its resultant cross-border operations (e.g., kidnapping Israeli soldiers) led to a war that proved to be devastating, mostly to Lebanon. If Hizballah tries to challenge Israel again, Israel should be ready to take strong action such as targeting the group’s commanders and headquarters in Lebanon—even if this runs the risk of intense fire exchanges or war.

Relevant preparations for this option should include increased monitoring of Hizballah officials—overtly and covertly—and perhaps even the transfer of some military units to the north. Hizballah needs to know that Israel is no longer shying away from conflict, since this may be the only way of forcing the group to return to the old, accepted rules of the game and step down from the precipice of a war that it does not appear to want.