The effort to find and destroy the last vestiges of the Islamic State in Iraq and al-Sham (ISIS) may have gotten its biggest boost since the fall of Raqqa. Using a ruse, Iraqi intelligence enticed five of its top leaders into a trap, capturing them all alive. The operation was the culmination of a joint effort with the US and Turkey, pointing out the potential fault lines as well as synergy the combination provides:

Iraq captured five Islamic State commanders after its intelligence services lured them into crossing from neighboring Syria, Iraqi state TV reported Wednesday.

It described the five as “some of the most wanted” leaders of ISIS. They were named as Saddam al-Jammel, Mohamed al-Qadeer, Ismail al-Eithawi, Omar al-Karbouli and Essam al-Zawbai and were shown in yellow prisoner uniforms. …

Hashimi said the operation was carried out in cooperation with U.S. forces, part of an American-led coalition fighting against Islamic State on both sides of the Iraqi-Syrian border.

Following Eithawi’s capture, Iraqi and American intelligence agents were able to uncover bank accounts used by the group and also secret communication codes he used, Hashimi said.

It all started with a tip about one leader who had been moving back and forth across the Turkish border using an assumed identity. Once identified and captured, intel resources from all three countries got key information from the detainee that led to the other leaders:

Mr. Ithawi, described by the Iraqis as a top aide to the Islamic State leader Abu Bakr al- Baghdadi, had been in charge of fatwas, or religious rulings, in the Islamic State’s so-called caliphate. He was also in charge of the education curriculum, and was a member of the body that appointed security and administrative leaders for the Islamic State’s territory, which had included large parts of Iraq and Syria.

He had been living in Turkey with his Syrian wife under his brother’s identity, one of these officials said.

The Iraqis sent the Turks an intelligence file they had amassed on Mr. Ithawi, and the Turkish security forces arrested him on Feb. 15, and extradited him to Iraq, this official said.

The interrogation paid specific military dividends even before the capture. Fortunately, that didn’t tip off ISIS command to their security breach:

The American-led coalition used this information to launch an airstrike in mid-April that killed 39 suspected Islamic State members near Hajin, in the Deir al-Zour district of Syria, the second official said.

The joint Iraqi-American intelligence team then set a trap, according to these officials. They persuaded Mr. Ithawi to contact several of his Islamic State colleagues who had been hiding in Syria and lure them across the border, the officials said.

The Iraqi authorities were waiting, and arrested the group soon after they crossed the frontier, the officials said.

Presumably the five men have been sufficiently interrogated prior to this announcement. Normally, intelligence agencies keep these kinds of victories under wraps until all the potential gets played out. Now that the other ISIS leaders know of their capture — or at least have had it confirmed on Iraqi TV — they will take steps to cover their rear ends, reshuffling their security and changing locations to keep the US coalition from capturing them next.

Or perhaps that’s the point. The biggest risk for insurgents is when they have to suddenly shift resources from previously safe havens. Moving opens up opportunities for intelligence and military assets in the area to pick them off. With their world shrinking down to almost nothing as it is, popping up on radar screens would be almost unavoidable.

Either way, this deals a big blow to ISIS’ command structure and their ability to maintain control. Abu Bakr al-Baghdadi’s leadership will lose even more credibility, and their ability to retain fighters and recruit new replacements will decline further. Hopefully this intelligence coup will spell the end of the group sooner rather than later.

Jim Geraghty asks a pretty good question in the wake of this news: