A frightening, far-reaching new world of terror threats since 9/11

Times have changed, and the terror landscape has changed with it.

Public Enemy No. 1, Osama bin Laden, is gone, killed by U.S. commandos in a 2011 Pakistan raid. The group he notoriously commanded no longer dominates. Sure, Ayman al-Zawahiri makes an occasional pronouncement, but other groups have garnered more than their share of chilling headlines for acts such as the failed underwear bomb plot on a Detroit-bound jetliner, the Westgate Mall siege in Kenya and the attack on a U.S. diplomatic compound in Benghazi, Libya.

In short, al Qaeda has a lot more competition these days — including from groups it inspired, it partners with and that splintered from it.

Fifty-nine groups on the U.S. State Department’s list of “Foreign Terrorist Organizations.” Some of them stand out for what they’ve said and done in the 13 years since the September 11, 2001, attacks, as well as for how Washington and its allies in the West have reacted to those actions. Here’s a look at some of those organizations:

ISIS

What is it?

How does a group show its hatred for its enemies, America included? How does it prove its willingness to do anything — even the most heinous acts imaginable — for its cause? How does it invoke terror, in the basest sense?

It acts like ISIS.

When it landed on the State Department list in 2004, the Abu Musab al-Zarqawi-led group was known as al Qaeda in Iraq and was known for attacking U.S. and allied forces, assassinating officials and beheading hostages. It suffered blows before being reborn as the Islamic State in Iraq, and later the Islamic State in Iraq and Syria, names that signified its new mission: to create a far-reaching caliphate.

From 2006: Al-Zarqawi killed in U.S. bombing raid

This shift was accompanied by a fresh focus on things such as providing food, health care and other necessities. Yet its tactics in handling nonbelievers and its foes did not change much.

The first terror group to build an Islamic state?

What has it done?

ISIS has taken advantage of instability in Syria, where it’s become one of the most feared groups trying to oust President Bashar al-Assad, and Iraq, where it has made inroads in opposition to Iraq’s unsettled, Shiite-led government, to take over vast swaths of territory.

This success has something to do with its appeal to dissatisfied Sunni Muslims. At the same time, a lot of its success stems from its using a brazen, often brutal and heavy-handed approach to force its will. This is an organization, after all, that’s been so ruthless even al Qaeda disowned it.

Six people died in that attack, a fraction of the nearly 3,000 killed eight years later in the 9/11 attacks when a pair of commercial airliners were flown into the Twin Towers in New York, another hit the Pentagon near D.C. and another crashed in Pennsylvania. Still, the 1993 attack was significant because it showed al Qaeda was willing and able to strike inside the United States.

Other attacks followed. The targets included U.S. troops, such as the USS Cole bombing and bombings at military bases in Saudi Arabia. More than 220 people died in twin 1998 truck bombings outside U.S. embassies in Kenya and Tanzania. And after 52 commuters died in two July 2005 attacks on London’s transit system, al-Zawahiri threatened that “more (destruction) will come, God willing.”

“Our message is clear — what you saw in New York and Washington (in 2001) and what you are seeing in Afghanistan and Iraq, all these are nothing compared to what you will see next,” al-Zawahiri said then.

From 2005: Al Qaeda threatens more UK, U.S. attacks

Since then, al Qaeda hasn’t pulled off a direct attack on the West on the scale of 9/11 or the London bombings. But it hasn’t been quiet either, even after the 2011 death of bin Laden. That includes various pronouncements — such as the forming of an al Qaeda affiliate for India — or partnering with or supporting other groups as they launch attacks of their own.

What’s been done about it?

There were efforts to disrupt al Qaeda before 2001, yet none significantly hampered its momentum or its leadership. As the 9/11 Commission notes, the “CIA broke up some al Qaeda cells (but) the core of bin Laden’s organization nevertheless remained intact.”

September 11 changed everything.

Weeks later, NATO invoked Article 5 for the first time — meaning everyone in the alliance was obliged to support the United States.

Soon, the United States and its allies had tens of thousands of troops in Afghanistan going after al Qaeda fighters and the Taliban government sheltering them. U.S. troops are still there 13 years later, though Obama has said combat operations will end this year.

The U.S.-led coalition tried to foil al Qaeda in other ways as well, including cutting off its funding and gathering as much intelligence as it could. By many measures, they have been successful as al Qaeda hasn’t been as active or as destructive as it was in the late 1990s and early 2000s.

But time and again, the world is reminded that it’s not just about al Qaeda any more. Other groups have emerged from its shadow and followed its lead.

Some are as ruthless, if not more so. Some are as dangerous, if not more so. Some are as zealous in their beliefs, if not more so.

All are reminders that the terror threat has not gone away.

CNN’s Chelsea J. Carter, Paul Cruikshank and Tim Lister contributed to this report.

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