MARY LOUISE KELLY, HOST:
To another story now. Abu Bakr al-Baghdadi was not the first commander of ISIS, but he was the one in charge when the group steamrolled into Iraq and Syria in 2014. That land grab allowed it to declare a state, an outlaw territory that drew thousands of recruits from around the globe. Now that President Trump has declared Baghdadi dead, NPR's Hannah Allam looks at his bloody legacy and what his death means for a movement that is trying to make a comeback.
HANNAH ALLAM, BYLINE: In 2010, the militia that would come to be known as ISIS was struggling. The leader had just been killed. The fighters were spent from years of battle - the U.S. military, rival jihadists, angry tribes. The incoming commander? A 38-year-old Iraqi known as Abu Bakr al-Baghdadi. Under his leadership, the militia not only regrouped, by 2014, it had captured land in Syria and Iraq for an audacious new project that would take it to the next level.
AARON ZELIN: He did something that was extremely taboo within the Muslim world by declaring that the caliphate was back and that he was the caliph.
ALLAM: That's Aaron Zelin of the Washington Institute for Near East Policy. He monitors ISIS. Muslims across the world condemned the so-called caliphate, but within extremist circles, Zelin says, this was a game-changer. ISIS now had bragging rights over rivals like al-Qaida.
ZELIN: One of their main arguments in this regard vis-a-vis, you know, al-Qaida was that, yes, you might have done the 9/11 attacks, but we're the ones who resurrected the caliphate.
ALLAM: Baghdadi ordered all other jihadist groups to fall under the Islamic State umbrella. Al-Qaida said no way.
AMARNATH AMARASINGAM: It was moving too fast. It was too violent. I think in a bizarre way, al-Qaida took a principled stance to say, these guys are just too extreme even for our taste.
ALLAM: Amarnath Amarasingam is a Canadian terrorism researcher. He's interviewed several Islamic State members and says that extreme reputation was part of the appeal, especially for young recruits, millennials who helped push the movement into the digital age.
AMARASINGAM: They would land in Syria and maintain their social media accounts, continue to post about their breakfast and what they were doing while being a member of ISIS.
ALLAM: Gone were the days of hand-smuggled tapes from mountain hideouts. Baghdadi, himself a rapist and a killer, let his followers post their own atrocities online in sickening clips that were stylized, even cinematic. Zelin, the researcher.
ZELIN: It's more like you're watching a TV show or movie. And also, it's not just focused on the specific leaders of the group but also just the random foot soldier or member.
AUDREY KURTH CRONIN: It wasn't all negativity and brutality.
ALLAM: That's Audrey Kurth Cronin, an American University professor who's written extensively about how militant groups decline. She says ISIS draws its resilience from the broader promise of an extremist utopia, a goal that's not tied to any single commander.
CRONIN: Anyone who thinks that the killing of al-Baghdadi is going to end ISIS really hasn't understood the nature of the group and really hasn't been doing - reading its history.
ALLAM: Another professor, Jenna Jordan at Georgia Tech in Atlanta, wrote a book about what happens to a terrorist group when the leader is removed. She found that the ones that survived tended to be more bureaucratic. They were built around ideology, not personality - in short, like ISIS, with or without Baghdadi.
JENNA JORDAN: The organization still exists. It still has a lot of operatives in Iraq and Syria and supporters globally, and that he was able to create that is incredible. That said, he created something that is able to withstand his death.
ALLAM: ISIS hasn't yet named a successor to Baghdadi, and it's unclear whether the next leader will share the same ruthless ambition that galvanized a generation of extremists.
Hannah Allam, NPR News. Transcript provided by NPR, Copyright NPR.