Experts say jihad likely to outlive IS

Veteran militants present long-term threat that the West is poorly prepared to cope with

Even if the Islamic State group is one day defeated on its territory, the world could face an even greater threat from tens of thousands of battle-hardened jihadist veterans, experts have warned.

US intelligence services estimate about 30,000 people have joined the ranks of IS from about 100 countries, adding to the huge number that have fought with older Islamic extremist groups over the decades.