The Islamic State has lost about 22 percent of its territory in Iraq and Syria in the past 15 months, according to a new study. In 2014, the extremist group exploited the power vacuums racking the region, surging into major cities on both sides of the Iraqi-Syrian desert border. Since then, its brutal massacres and myriad acts of destruction have sparked global outrage and prompted more than a year of airstrikes by a U.S.-led coalition.

Now, according to a report from IHS Jane's 360, the tide is decisively turning against the extremist organization. Despite a territorial advance last summer in parts of Iraq and Syria, the Islamic State has suffered significant setbacks — as the regions marked in red in the map above show. IHS estimated that the Islamic State lost about 14 percent of the territory under its control in 2015 and a further 8 percent in the first three months of this year.

The monitoring group attributes these defeats to a changing strategic landscape. The loss of the pivotal Syrian border crossing of Tal Abyad took out one of the Islamic State's chief access points for smuggling in weapons, materiel and new fighters. Tighter Turkish border controls also have thinned out cash flows, as well as the numbers of foreign recruits seeking to join the group.

Airstrikes by the U.S.-led campaign and an ongoing Russian mission in Syria have pinned the Islamic State back. With that support, Syrian Kurdish factions allied with a number of Arab outfits have pushed against the militants in Syria's northeast; the Iraqi military, backed by Iranian-sponsored Shiite militias, has reclaimed key cities in the heart of Iraq; and government troops loyal to Syrian President Bashar al-Assad are approaching the central city of Palmyra, home to an ancient heritage site the Islamic State seized and started ransacking last year.

"Isolation and further military defeats will make it harder for the Islamic State to attract new recruits to Syria from the pool of foreign jihadis," writes Columb Strack, a Middle East analyst at IHS.

But the demise of the Islamic State is hardly a foregone conclusion. As a separate report from the Institute for the Study of War points out, the threat posed by the extremists is not limited by geography. Even as the group suffered defeats in Iraq and Syria, its proxies carried out brazen attacks from Jakarta to Paris and numerous other places in between.

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