Video Appearing to Show Jordanian Pilot's Burning Death 'Absolutely' Backfired Against ISIS

— -- The ISIS video appearing to show a Jordanian pilot being burned alive “absolutely” backfired on the terror group, retired Marine Corps General John Allen told ABC News in an exclusive interview.

“It will be one of these moments that created a unity of purpose and a unity of effort among the nations [of the world,]" Allen, the Special Presidential Envoy for the Global Coalition to Counter ISIS, said from Amman, Jordan.

Allen arrived in Jordan to meet with King Abdullah and other officials after ISIS released video appearing to show Jordanian pilot Lt. Muath al-Kasabeh being burned alive while trapped in a cage. The video triggered outrage around the world and spurred Jordan to take more action against the terror group.

“King Abdullah has indicated the desire to do more in the aftermath of this horrific killing,” Allen said. “He’s been a leader in this process.”

With Jordan conducting more airstrikes over Syria, Allen believes “it’s galvanized the coalition” fighting ISIS.

The importance of forging a strong coalition is a lesson Allen knows well. In Iraq, he helped unite Sunni tribes in the fight against al Qaeda and formed relationships with Middle Eastern leaders who are now involved in the fight against ISIS.

But until the past week, Allen faced difficulties in forming a true coalition. The U.S. has been responsible for more than 80 percent of all the air strikes against ISIS.

While ISIS has now been run out of Kobani, Syria, by Kurdish forces, much of the country remains a battle ground.

“It’s a very important concern. We don’t have a partner in Syria as we do in Iraq,” said Allen.

Even in Iraq, ISIS controls one-third of the country and it remains to be seen if Iraqi security forces are capable of retaking territory.

“We work very hard at several levels to prepare the Iraqi security forces to do this. We have advise and assist elements that are with them today,” Allen said. “There are elements of the Iraqi security forces that are in fact in action today.”

Allen also believes that ISIS’s own actions – like the video of al-Kasabeh's purported death – will help defeat them, saying the terror group “is beginning to eat itself with increasing numbers of reports of ISIL executing foreign fighters who have come from long distances to be part of this.”

But the shadow of ISIS has far reach. When asked if the terror group remains a threat to the homeland, Allen said, “I think we should take it very seriously.”