The countries with the highest number of fighters this year are Syria (43,650 to 70,550), Afghanistan (27,000 to 64,060), Pakistan (17,900 to 39,540), Iraq (10,000 to 15,000), Nigeria (3,450 to 6,900) and Somalia (3,095 to 7,240), the report said.
Of the various Salafi jihadist groups, the Islamic State remains the predominant threat, with as many as about 40,000 members globally this year, up from 30,200 in 2014, when the group’s fighters seized the northern third of Iraq.
That figure is even higher than those of other recent studies. Data collected by the Pentagon and the United Nations this year indicated that the Islamic State has as many fighters now as it did in 2014 — the peak of the caliphate — with 20,000 to 31,500 members in Iraq and Syria alone, and thousands more spread across the numerous other countries where it has implanted itself. Senior officials at the Pentagon and in the White House, however, say the real number is far lower.
Despite these large numbers of fighters, an examination by The New York Times in September found that Islamic State attacks in the West have fallen sharply in 2018 compared with the previous four years, the first time the number has fallen since 2014. But the number of attempted attacks remained steady, suggesting that the group remains committed to carrying out devastating harm.
Tens of thousands of Islamic State members — including senior leaders, veteran field commanders and foreign fighters — have been killed in United States airstrikes and partner actions. The extremist group now holds less than 1 percent of the territory it seized in Iraq and Syria in 2014, or about half the area of Manhattan.
But an American-backed military offensive stalled this month against the Islamic State’s last vestige in eastern Syria. The Syrian Democratic Forces, the Kurdish-led militia that is fighting the Islamic State with American help, suspended operations after Kurdish positions farther north were shelled by Turkey — not far from United States advisers. But the militia says it will resume its fight.
“Americans should understand that terrorism won’t end,” the report concluded, “even though the terrorism threat may ebb and flow.”