Social media and other technology are making it increasingly difficult to combat "extremists" who are using such modern resources to share information and conduct operations, the head of the US Central Intelligence Agency (CIA) has said.
John Brennan, the CIA director, said such communications only added to the difficulty of dealing with diffuse threats and attacks across the world from groups like the Islamic State of Iraq and the Levant (ISIL) and others.
"New technologies can help groups like ISIL coordinate operations, attract new recruits, disseminate propaganda, and inspire sympathisers across the globe to act in their name," Brennan said.
"The overall threat of terrorism is greatly amplified by today's interconnected world, where an incident in one corner of the globe can instantly spark a reaction thousands of miles away; and where a lone extremist can go online and learn how to carry out an attack without ever leaving home," Brennan said.
Speaking at the Council on Foreign Relations in New York, Brennan cited a recent spate of attacks, including shootings at the French satirical newspaper Charlie Hebdo, at a cafe in Copenhagen, Denmark and a Pakistani school.
"These attacks underscore a disturbing trend that we have been monitoring for some time: The emergence of a terrorist threat that is increasingly decentralised, difficult to track, and difficult to thwart."
The security concerns over the last year underscore an increasingly volatile world with more outbreaks of instability since the fall of the Soviet Union, Brennan said.
And while agencies such as the CIA have worked to boost their capability of fighting cyber-based threats, those bent on committing "acts of terror" have used technologies to romanticise their ideology, he added.
"A lot of it is inconsistent with realities of Iraq and Syria. But this phenomenon now has generated a lot of appeal."
Call for cooperation
Brennan said governments would have to work with private industry and other partners to identify and track down extremists, pointing to the ongoing conflict in Syria and Iraq and the challenge of foreign fighters engaging in the conflict there as a top priority.
The director also said that intelligence was not the only solution to global instability.
"What we need to be able to do is to help policy makers understand some of the forces that are at play and how certain developments and actions may affect that calculus. And that's what I think is important for the CIA," said Brennan.
The CIA has stepped up its expertise in cyberspace, creating new units within the agency called "mission centres", intended to concentrate focus on specific challenges or geographic areas, such as weapons proliferation or Africa.