On Tuesday, the US military cautiously celebrated what has the potential, if confirmed, of being a major victory in the fight against ISIS.

A US airstrike on Tuesday was believed to have killed ISIS’s “minister of war” Abu Omar al-Shishani, also called Omar the Chechen.

If true, such a strike will both seriously hinder ISIS’s tactical abilities on the ground as well as the group’s ability to recruit foreign fighters from the Caucus regions.

Aside from ISIS’ ‘caliph’ Abu Bakr al-Baghdadi, the Georgian ex-commando Omar al-Shishani was the most recognizable and popular of the powerful militant group’s leaders.

Sporting a recognizable red beard and happy to pose for photos, Shishani has acted as a very public face for some of ISIS’ most notorious successes.

It was Shishani who posed with the stolen US Humvees that ISIS had seized from Mosul and brought back into Syria.

And it was Shishani who had led successful ISIS military campaigns throughout Syria as well as a blitz through western Iraq that put the group within 100 miles of Baghdad.

These military successes are not simply the result of any innate military capabilities. Instead, Shishani spent years conducting military campaigns against the Russians, first as a Chechen rebel and then as a soldier in the Georgian military. During Shishani’s four years in the military, from 2006 to 2010, his unit received some degree of training from American special forces units.