For, in one sense, the terrorists are fighting smarter than we are.These extremists use arms to fight their battles in the short term, but, to hold ground in the long run, they also fight Western education and women's empowerment.

They know that illiteracy, ignorance and oppression of women create the petri dish in which extremism can flourish.That's why the Islamic State kidnapped Samira Salih al-Nuaimi, a brave Iraqi woman and human rights lawyer in Mosul, tortured her and publicly executed her last week.

That's why the Taliban shot Malala Yousafzai, then 15 years old, after she campaigned for educating girls. And that's why Boko Haram kidnapped hundreds of schoolgirls in northern Nigeria and announced it would turn them into slaves.

In each case, the extremists recognised a basic truth: Their greatest strategic threat comes not from a drone but from a girl with a book. We need to recognise, and act on, that truth as well.

For similar reasons, the financiers of extremism have invested heavily in fundamentalist indoctrination. They have built Wahhabi madrassas in poor Muslim countries such as Pakistan, Niger and Mali, offering free meals, as well as scholarships for the best students to study in the Gulf.

Shouldn't we try to compete? Shouldn't we use weapons in the short run, but try to gain strategic advantage by focusing on education and on empowering women to build stable societies less vulnerable to extremist manipulation?

The United States air strikes have slowed the advance of the Islamic State and averted a genocide against the Yazidi population in Iraq, but it's very difficult to win a war from the air. That's why the Taliban still thrives in Afghanistan after 13 years of US air attacks.

Unfortunately, we're not playing the long game, as the extremists are. We are vastly overrelying on the military toolbox and underemploying the education toolbox, the women's empowerment toolbox, the communications toolbox. We're tacticians; alas, the extremists may be better strategists.

It's not a question of resources, because bombs are more expensive than books. The US military campaign against the Islamic State will cost at least $US2.4 billion a year and perhaps many times that, according to an estimate from the Centre for Strategic and Budgetary Assessments in Washington.

In contrast, Obama seems to have dropped his 2008 campaign promise to establish a $US2 billion global fund for education. And the United States gives the Global Partnership for Education, a big multilateral effort, less in a year than what we spend weekly in Syria and Iraq.

This is an area in which Congress seems more forward-looking than the president because Congress regularly appropriates substantially more for basic education overseas than Obama requests. Bipartisan legislation, the Education for All Act, would elevate the matter; let's hope Obama gets behind it.

No one is naive enough to think education is a panacea. Al-Qaeda leaders, including Osama bin Laden and Ayman al-Zawahri, have been university educated. Iraq, Syria and Lebanon were all reasonably well-educated and supportive of gender equality by regional standards, yet all have been torn apart by civil wars.

Still, the historical record of the past half-century is that education tends to nurture a more cosmopolitan middle class and gives people a stake in the system. In Hong Kong today, we're seeing how educated youth often behave. They are demanding democracy, but peacefully.

Girls' education seems to have more effect than boys' education, partly because educated women have markedly fewer children. The result is lower birthrates and less of a youth bulge in the population, which highly correlates to civil conflict.

I support judicious air strikes in the short term against the Islamic State, but that should be only one part of a policy combating extremism. And a starting point should be to ensure that the 3 million Syrian refugees mostly in Turkey, Jordan and Lebanon - especially girls - can get schooling.

Right now, many are getting none, and one study published last month found Syria had the worst reversal in educational attainment in recent history, with enrolment rates for Syrian children in Lebanon less than half of those in sub-Saharan Africa.

Yet the UNICEF request for education funding for Syrians was only 40 per cent financed as of mid-August. If we miss this opportunity, those children will be tinder for future wars and extremism, and we'll be stuck dropping bombs for generations to come.

So let's learn from the extremists - and from those brave girls themselves who are willing to risk their lives in order to get an education. They all understand the power of education, and we should, too.