Columnist

This week's tragic terrorist attack in New York was the kind of isolated incident by one troubled man that should not lead to generalizations. In the 16 years since 9/11, the city has proved astonishingly safe from jihadist groups and individuals. And yet, speaking about it to officials in this major global hub 10,000 miles away, the conclusions they reach are worrying. "The New York attack might be a way to remind us all that while ISIS is being defeated militarily, the ideological threat from radical Islam is spreading," says Singaporean Home Minister K. Shanmugam. "The trend line is moving in the wrong direction."

The military battle against Islamist extremist groups in places such as Syria and Afghanistan is a tough struggle, but it has always been one that favored the United States and its allies. After all, the combined military forces of some of the world's most powerful governments are up against a tiny band of guerrillas. On the other hand, the ideological challenge from the Islamic State has proved far more intractable. The terrorist group and ones like it have been able to spread their ideas, recruit disaffected young men and women, and infiltrate countries across the globe. Western countries remain susceptible to the occasional lone wolf, but the new breeding grounds of radicalism are once-moderate Muslim societies in Central, South and Southeast Asia.

Consider Indonesia, the world's most populous Muslim country, long seen as a moderate bulwark. This year, the governor of Jakarta, the country's capital and largest city, lost his bid for reelection after he was painted by Muslim hard- ­liners as unfit for office because he is Christian. Worse, he was then jailed after being convicted on a dubious and unfair blasphemy charge. Amid a rising tide of Islamist politics, Indonesia's "moderate" president and its mainstream "moderate" Islamic organizations have failed to stand up for the country's traditions of tolerance and multiculturalism.

Or look at Bangladesh, another country with a staunchly secular past, where nearly 150 million Muslims live. Founded as a breakaway from Pakistan on explicitly nonreligious grounds, Bangladesh's culture and politics have become increasingly extreme over the past decade. Atheists, secularists and intellectuals have been targeted and even killed, blasphemy laws have been enforced, and a spate of terrorist attacks have left hundreds dead.

Why is this happening? There are many explanations. Poverty, economic hardship and change produce anxieties. "People are disgusted by the corruption and incompetence of politicians. They are easily seduced by the idea that Islam is the answer, even though they don't know what that means," a Singaporean politician explained to me. And then, the local leaders make alliances with the clerics and give platforms to the extremists, all in search of easy votes. That political pandering has helped nurture a cancer of Islamist extremism.

In Southeast Asia, almost all observers whom I have spoken with believe that there is another crucial cause — exported money and ideology from the Middle East, chiefly Saudi Arabia. A Singaporean official told me, "Travel around Asia and you will see so many new mosques and madrassas built in the last 30 years that have had funding from the Gulf. They are modern, clean, air-conditioned, well-equipped — and Wahhabi [Saudi Arabia's puritanical version of Islam]." Recently, it was reported that Saudi Arabia plans to contribute almost $1 billion to build 560 mosques in Bangladesh. The Saudi government has denied this, but sources in Bangladesh tell me there's some truth to the report.

How to turn this trend around? Singapore's Shanmugam says that the city-state's population (15 percent of which is Muslim) has stayed relatively moderate because state and society work very hard at integration. "We have zero tolerance for any kind of militancy, but we also try to make sure Muslims don't feel marginalized," he explained. Singapore routinely gets high marks in global rankings for its transparency, low levels of corruption and the rule of law. Its economy provides opportunities for most.

Asia continues to rise, but so does Islamist radicalism there. This trend can be reversed only by better governance and better politics — by leaders who are less corrupt, more competent and, crucially, more willing to stand up to the clerics and extremists. Saudi Arabia's new crown prince spoke last week of turning his kingdom to "moderate Islam." Many have mocked this as a public-relations strategy, pointing to the continued dominance of the kingdom's ultra-orthodox religious establishment. A better approach would be to encourage the crown prince, hold him to his words and urge him to follow up with concrete actions. This is the prize. Were Saudi Arabia to begin religious reform at home, it would be a far larger victory against radical Islam than all the advances on the battlefield so far.

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