The death of Islamic State leader Abu Bakr al-Baghdadi marks the demise of one of the most brutally effective jihadist leaders of modern times — a man who at least loosely commanded tens of thousands of fighters from around the world, carved out a territorial caliphate in the Middle East, and refined a horrific ideology that survives him.

He was the world’s most-wanted terrorist, with a $25 million US bounty on his head, yet his capability to run the day-to-day affairs of the Islamic State was limited. Constantly under pressure, he was said to have had to move among various safe houses with a small group of loyalists and avoided using electronic communications that could be tracked by intelligence agencies.


But he was an imposing figurehead, and his ability to elude the world’s most powerful intelligence services for so many years added to his mystique among his followers. He will be hard to replace.

His death is a major blow, but the extremist group has survived the loss of previous leaders and military setbacks going back to the aftermath of the 2003 US-led invasion of Iraq. Today, the group is diminished and scattered, pummeled through years of US airstrikes and by quick raids and brutal street-by-street battles with Kurdish and Iraqi forces. Baghdadi never publicly designated a successor, and many of his top deputies have been killed. His death could spark infighting among prospective successors, potentially further weakening the group.

Yet, the Islamic State group, also known as ISIS, in its various forms has survived the death of several leaders and senior commanders. It has been able to replenish its ranks by attracting Sunni Muslims in the Middle East who feel oppressed by their governments, as well as foreigners attracted by the group’s austere vision of Islam, its ultra-violent tactics, or both.


It still boasts powerful affiliates in other countries and remnants of the original group continue to carry out sporadic attacks in both Syria and Iraq.

Perhaps even more worrying are the tens of thousands of Islamic State fighters and supporters detained across the Middle East, including those held by Kurdish fighters in eastern Syria. The US decision this month to pull out of Syria and abandon its former allies to a Turkish invasion allowed hundreds of Islamic State supporters to escape and raised concerns about the security of other facilities.

It’s possible that a future Islamic State leader is wearing a prison jumpsuit, quietly recruiting supporters within concrete walls lined with barbed wire and plotting his next move — just as Baghdadi once did.

Born Ibrahim Awwad Ibrahim Ali al-Badri al-Samarrai in 1971 in Samarra, Iraq, he adopted the nom de guerre al-Baghdadi and joined the Sunni insurgency against US forces after the 2003 invasion. He was detained by US troops in February 2004 and spent 10 months in the Camp Bucca prison in southern Iraq.

He eventually assumed control of the Islamic State of Iraq, an Al Qaeda-linked group founded by Abu Musab al-Zarqawi, a Jordanian militant killed in a US airstrike in Iraq in 2006. Under Baghdadi, the group expanded into neighboring Syria, exploiting the chaos unleashed by that country’s 2011 uprising and civil war.

In the summer of 2014, his fighters swept across eastern Syria and northern and western Iraq, eventually carving out a self-styled ‘‘caliphate’’ in a third of both countries. In early July, Baghdadi made his first public appearance, delivering a sermon in a centuries-old mosque in the Iraqi city of Mosul and declaring himself caliph, or leader of the world’s Muslims.


Under his leadership, the group carried out a wave of atrocities, including the enslavement and rape of thousands of women from Iraq’s Yazidi minority. They massacred captives, beheaded journalists, including James Foley of New Hampshire, and aid workers. They threw individuals believed to be gay from the rooftops of buildings. They gleefully broadcast the killings with slickly produced videos and photos on social media.

Baghdadi repeatedly urged his followers to attack a list of enemies that came to include much of the world, including the United States and other Western countries, Shi’ite Muslims, whom he deemed apostates, and even devout Sunni Muslims who rejected his group’s ideology.

Unlike Osama bin Laden and other jihadists who strove to carry out 9/11-style attacks that would capture world attention, Baghdadi exhorted followers to do whatever they could with the weapons they had at hand. His group claimed scores of attacks worldwide, including so-called lone-wolf attacks with no direct connection to the group.

But the Islamic State also directly orchestrated attacks, including the 2015 shootings and suicide bombings in Paris that killed 130 people. It also claimed this year’s Easter suicide bombings in Sri Lanka that killed 269 people.

The extremist group attracted tens of thousands of foreigners to whom it provided advanced military training, and spawned powerful affiliates in Egypt, Libya, Afghanistan, and elsewhere that continue to carry out attacks.