WASHINGTON – Losing real estate in the Middle East will not sharply affect Islamic State militants' ability to inspire attacks against the West or burrow footholds from the Philippines to Africa, which has forced the U.S. to spread its resources thinly around the world, the nation's top counterterrorism official said Friday.
IS is an "adaptable" organization that knew it would lose cities in Syria and Iraq, Nicholas Rasmussen, the National Counterterrorism Center director, said. He spoke after Kurdish-led forces declared victory over IS in Raqqa, the former Syrian "capital" of its self-proclaimed caliphate where militants terrorized the population for four years.
In an interview on on C-SPAN's "Newsmakers" that airs Sunday, Rasmussen said ISIS these days mostly inspires individuals overseas to act in the name of the group. In this way, it differs from al-Qaida, which runs a clandestine network that carefully vets members. The Islamic State sets low barriers for entry.
"If you say you're ISIS and you want to act on ISIS' behalf, you're in," Rasmussen said, saying the group's ability to inspire individuals won't dry up because of battlefield losses.
In the U.S., the greatest threat from IS isn't sleeper cells, but individuals inspired or motivated by the group's ideology, he said. He said extremists remain preoccupied with aviation, "part of the terrorist problem set that I think gives me the most concern every day."
Rasmussen said the group can still operate in a degraded form.
"Our assessment is that there is still a command-and-control apparatus at senior levels of ISIS," Rasmussen said. It has been forced to relocate, making it harder for the group to communicate with overseas affiliates and colleagues worldwide.
But it has created an organizational bureaucracy, including a sector guiding global operations. "We have made that less effective, but we have not eliminated it," Rasmussen said.
One of IS' priorities is creating a presence in West Africa, where an ambush killed four U.S. soldiers two weeks ago. No extremist group has claimed responsibility for the deadly ambush.
Rasmussen said IS has worked to use the existing terror platform created by Boko Haram, another Islamist extremist organization already present throughout West Africa. IS's push into the region doesn't directly threaten the U.S. homeland, but Rasmussen said Washington worries the group will carve out a haven there and replay its campaign in Iraq and Syria.
"Control of territory would, over time, give the organization the ability to carry out more ambitious attacks that might ultimately threaten U.S. interests," he said.
The U.S. has about 1,000 troops in that part of Africa to support a French-led mission to disrupt and destroy extremist elements. The U.S. provides aerial refueling, intelligence and reconnaissance support, and ground troops to engage with local leaders.
IS's global reach makes it a challenging adversary, forcing the U.S. to spread its diplomatic, military and intelligence resources "more thinly" around the world than in the past, Rasmussen said.
It is moving into northern Africa, joining forces with extremists operating in places such as Libya, Algeria and Morocco, he said. While these groups are seen as local, not transnational threats, Rasmussen said: "You don't have to look too closely at a map to see that north Africa edges up pretty close to Europe."
He recently returned from a trip to Southeast Asia where Philippine troops have been crushing a final stand by the last dozens of pro-Islamic State group militants in a southern city. Still, he said threat there is escalating.
"There's certainly a capacity within Southeast Asia for extremism to manifest itself into terrorism and if IS taps into that successfully, it could create a regional threat of the sort we haven't seen in the last several years," Rasmussen said.