Global war on terror rages as ISIS, al Qaeda expand 23 years after 9/11

The Sept. 11, 2001 terrorist attacks on the U.S. by al Qaeda jihadists changed the future of security for not only Washington, but for nations on every inhabited continent worldwide — sparking the Global War on Terror that continues to this day.

More than 20 years have passed since 19 hijackers boarded four commercial flights and crashed into the Twin Towers in New York City, the Pentagon near Washington, D.C., and an empty field in Pennsylvania after passengers on United Airlines flight 93 thwarted what is believed to have been an attempt to strike either the U.S. Capitol or the White House. 

The plan, outlined by al Qaeda leader Osama bin Laden, killed 2,977 victims 23 years ago in what remains the largest terrorist attack in history and set in motion a global fight against extremism.

But despite the end to the U.S. war in Afghanistan and declared defeat over Islamic terrorist organizations like al Qaeda and the Islamic State, experts warn the threat posed by extremist groups remains acute to this day.

Pedestrians in lower Manhattan watch smoke billow from New York's World Trade Center on Tuesday, Sept. 11, 2001.  (AP Photo/Amy Sancetta)

TOP GENERAL IN FIGHT AGAINST THE TALIBAN SAYS AFGHANISTAN HAS ONCE AGAIN BECOME A ‘CRUCIBLE OF TERRORISM’

"The threat has evolved," Bill Roggio, senior fellow with the Foundation for Defense of Democracies and editor of the Long War Journal, told Fox News Digital. "It's certainly much more difficult to launch a 9/11 style attack, but there's much more opportunity for jihadists from both al Qaeda and the Islamic State to launch individual attacks, such as we've witnessed over the last decade and a half particularly. 

 "Prior to 9/11, al Qaeda was operating openly in Afghanistan and on cellular level, in dozens of countries. And now there are safe havens and battlefields with 10s of 1000s of fighters that exist throughout the world," he added.

The 2024 Global Terrorism Index released by the Institute for Economics & Peace in February analyzed the effects of terrorism over the previous year and found that deaths from terrorism increased by 22% from 2022 and "are now at their highest level since 2017."

In this 1998 file photo, Usama bin Laden speaks to the journalists in Khost, Afghanistan and made available Friday March 19, 2004. A person familiar with developments said Sunday, May 1, 2011 that bin Laden is dead and the U.S. has the body. (Mazhar Ali Khan/AP)

The jump in terrorist-related deaths last year, which does include the Oct. 7 Hamas attacks on Israel, are still 23% lower than at the global peak seen in 2015, though the Institute only began releasing the GTI report over a decade into the Global War on Terror in 2012.

While attacks by terrorist groups are once again on the rise and there is immense terrorist activity in the Middle East with the war between Israel and Hamas, Iran’s vigorous backing of terrorist groups like Hezbollah, the Taliban takeover of Afghanistan and subsequent safe haven granted to al Qaeda, and continuous ISIS attacks in Iraq and Syria against coalition forces, the Middle East is no longer the "epicenter" of terrorist activity.

Syrian Kurdish security forces stand by as former detainees suspected of being members of the Islamic State (IS) group are released in Syria's northeastern city of Hasakeh on Sept. 2, 2024.  (DELIL SOULEIMAN/AFP via Getty Images)

"The epicentre of terrorism has shifted from the Middle East and North Africa into sub-Saharan Africa, concentrated largely in the Sahel region. This region now accounts for almost half of all deaths from terrorism globally," the GTI report found, noting that deaths from terrorism in the Sahel grew by 38% in 2023 from 2022.

Complex security and humanitarian crises driven by poor regional leadership and immense economic hardship have created a vacuum in places like Burkina Faso — which alone accounted for nearly a quarter of all terrorism related deaths globally, as over 1,900 people were killed in 258 reported incidents last year.

2023 marked the first time since the Institute began releasing the GTI report over a decade ago that a country other than Afghanistan or Iraq was listed at the top of the index as the nation most impacted by terrorism in 2023.

A masked Islamic State soldier poses holding the ISIS flag in 2015. (History/Universal Images Group via Getty Images)

3 YEARS AFTER US WITHDRAWAL FROM AFGHANISTAN, ISRAEL LOOKS TO LESSONS LEARNED FROM WAR ON TERROR

The State Department assesses that ISIS-Sahel and JNIM, an al Qaeda affiliate, are the most active terrorist groups in Burkino Faso, with JNIM having taken credit for the majority of claimed attacks in the country. 

Though Burkina Faso was also ranked among the nations globally where attacks were not attributed to any specific group — a trend most seen in areas where ISIS operates.

Charles Lister, Director of the Syria and Countering Terrorism & Extremism programs at the Middle East Institute (MEI), explained ISIS is one of the first terrorist organizations ever to routinely not claim credit for its attack in a "clear attempt to conceal its activities from the international community."

A member of the Kurdish security forces stands guard in September 2023 as released detainees prepare to leave the Kurdish-run al-Hol camp, which holds relatives of suspected Islamic State fighters in Syria's northeastern Hasakeh governorate. (Delil Souleiman/AFP via Getty Images)

ISIS was declared defeated in December 2018 by Donald Trump, but experts have been sounding the alarm that the terrorist group is continuing to grow and expand its influence globally.

"We inflicted at best…an operational or tactical defeat. We did not inflict a strategic defeat on the Islamic State," Retired Lt. Gen. Michael Nagata, former Commander of U.S. Special Operations Command Central (SOCCENT) and an MEI Distinguished Senior Fellow on National Security, said during an event hosted by MEI on Tuesday. 

"The evidence for our failure to inflict a strategic defeat of the Islamic State is best demonstrated by the fact we now have ISIS franchises stretching all the way from the western coast of Africa to the entire area of South Asia," he added. "No other terrorist group, in my experience, has ever been able to build a global network of that size, sophistication, capable of using modern technology to conduct terrorist activities." 

ISIS THREAT RISING IN SYRIA, IRAQ AS US MILITARY WARNS TERROR ATTACKS COULD DOUBLE IN 2024

An Ivorian soldier provides security on the arrival of Ivorian Prime Minister Patrick Achi at the launch of a vast aid plan for young people in regions bordering Mali and Burkina Faso where jihadist groups are trying to recruit, in Tougbo, on Jan. 22, 2022. (Sia KAMBOU / AFP)

Attacks by IS and its affiliates accounted for 14% of all attacks worldwide last year according to the GTI report — a figure it also noted was likely much higher in reality.

"[ISIS] has managed to tap into local conflicts and ungoverned spaces in a way that we’ve never seen al Qaeda succeed," Lister, a senior fellow with MEI told reporters this week. "I think that’s real cause for concern."

ISIS, like other Islamic terrorist organizations including al Qaeda, has the strategic aim of collecting territory for the purpose of establishing a caliphate — a governing system based on strict interpretations of Sharia law. 

Terrorists participate in military training in this undated still frame from a recruitment video for Usama Bin Laden''s extremist Al Qaeda network.  (Al Rai Al Aam/Feature Story News/Getty Images)

Though despite its expansion outside the Middle East, the nation most affected by the Islamic State is still Syria, where U.S. and coalition forces continue to combat the terrorist network. 

The U.S., in coordination with allied forces in Iraq and Syria, have engaged in some 200 operations against ISIS this year alone, the majority of which have been carried out in Iraq. 

Though despite the upswing in anti-ISIS missions in Iraq, the Pentagon this week confirmed it is in discussions with Iraqi officials over the complete withdrawal of U.S. forces by September 2025.

Houthi followers burn the Israeli and American flags during a tribal gathering on January 14, 2024 on the outskirts of Sana'a, Yemen. Houthi followers gathered to protest against the U.S.-U.K. airstrikes on positions in areas under their control.  (Mohammed Hamoud/Getty Images)

Currently, there are some 2,500 U.S. troops in Iraq that work with Iraqi security forces and the Kurdish security forces to carry out the Defeat ISIS Mission, along with another 900 U.S. forces in Syria.

But security experts are deeply concerned over how this withdrawal could negatively affect the mission in Syria — an area where the U.S. and coalition forces already have a more difficult time countering ISIS efforts, in part due to Iran-backed militias.

"That will have a knock-on effect on our ability to operate in Syria. It will likely mean we will leave Syria, and then we've got a whole lot of things to worry about," warned Lister.

The expert warned the only way to combat ISIS is to work with a coalition of nations to collect better intelligence and work against the terrorist group.

But ultimately, Nagata warned ISIS will remain until nations figure out a way to address deeper socio-economic and human rights-based issues.

"The hardest thing about dealing with a terrorist group, particularly one as gifted as the Islamic State, is defeating their idea, and that is not something that you do with a rifle or a hand grenade or a missile strike," he said. "We could tactically defeat them until the cows come home, and it won't solve the problem," he said.

Caitlin McFall is a Reporter at Fox News Digital covering Politics, U.S. and World news.