Shortly before midnight on May 1, 2011, President Barack Obama stood at a lectern in the East Room of the White House and delivered a startling announcement: American forces had located — and killed — the most wanted terrorist on the planet, Osama bin Laden.
Obama briefly described the operation, then he reminded viewers of how notable it was that the man who helped found the most well-known terrorist organization around — al Qaeda — and orchestrated the mass-murder of more than 3,000 people on Sept. 11, 2001, was gone.
"For over two decades, bin Laden has been al Qaeda's leader and symbol, and has continued to plot attacks against our country and our friends and allies," Obama said. "The death of bin Laden marks the most significant achievement to date in our nation's effort to defeat al Qaeda."
Yet five years later, militant Islamic extremism has hardly receded. Here are three important developments since bin Laden's death.
Rise of ISIS
The group surged onto the international stage two years ago with a series of brutal, headline-grabbing events — mass executions, beheadings, and enslavement. As it amassed territory in Iraq and Syria, its once al Qaeda-affiliated leader, Abu Bakr al-Baghdadi, declared the group a caliphate.
Baghdadi's announcement marked a new chapter in an ancient pattern for Islamic extremism. And unlike Bin Laden's replacement, Ayman al-Zawahiri, jihadis heralded Baghdadi as a commanding presence. "He's a fighter, he's a warrior," Shashank Joshi, a research fellow at the London-based Royal United Services Institute think tank, told NBC News last year. "He's carved out the state, whereas Zawahiri is seen as someone who is on the run."
While air strikes in Iraq and Syria have stripped ISIS of some of its territory, Aaron David Miller, a former Middle East negotiator and scholar with the Wilson Center, told NBC News that the group has "jumped borders" and is "broader and deeper than we probably know." It also claimed responsibility for the terror attacks in Paris, Brussels and Egypt, while in Nigeria Boko Haram has pledged allegiance to the group, as did Tashfeen Malik, who helped kill 14 people and injure 22 more in San Bernardino, California in December.
Al Qaeda Resurgence?
ISIS may have dominated news coverage in recent years, and al Qaeda's core may have lost significant ground in Pakistan, but security officials and terrorism experts worry that the group's far-flung affiliates in countries like Yemen and Syria are poised for a comeback that may pose an even greater threat to the U.S. than al-Baghdadi's so-called caliphate.
Former CIA scholar-in-residence for counterterrorism Bruce Hoffman told NBC News earlier this year that the group's Syrian affiliate, Jabhat al Nusra, is "more dangerous and capable than ISIS."
A recent report from the Institute for the Study of War, a Washington think tank, put it this way: "Al Qaeda is pursuing phased, gradual, and sophisticated strategies that favor letting ISIS attract the attention — and attacks — of the West while it builds the human infrastructure to support and sustain major gains in the future and for the long term."
Guantanamo and Terror Recruitment
President Obama has been trying to close the prison facility at the U.S. Naval Station Guantanamo Bay in Cuba since before Bin Laden's death. "It is viewed as a stain on our broader record of upholding the highest standards of rule of law," he said in December. While his argument has hinged on humanitarian grounds, Obama has also described Gitmo as "one of the key magnets for jihadi recruitment."
Frank Cilluffo, director of George Washington University's center for cyber and homeland security, told NBC News that may have been true with al Qaeda several years ago, but ISIS has developed a different message and marketing strategy to reach would-be jihadis. Where the former would have pounded on the West's hypocrisies through videos reminiscent of "Blair Witch Project" or a 1970s-era magazine, Cilluffo said, ISIS offers up highly-produced films that use sophisticated cameras, multiple angles and sharp lighting to depict horrific events, such as beheadings and burnings. They're then uploaded to multiple social media platforms.
"It looks like you're playing a war game," he said. "They're trying to lionize war fighters."
These were produced alongside what Cilluffo described as "tourist videos" for Syria — footage that showed ISIS fighters taking care of children, for instance. "They're trying to show you you can have a decent life there," he said, adding that that message has changed as the group has ceded territory. "Now you're starting to see, 'If you can't come here, you can stay there and cause harm in the West."