Thwarting Terrorist Threats at Home

September 11, 2001 (9/11), with the tragic loss of nearly 3,000 lives, was the worst attack on American soil since the Japanese attacked Pearl Harbor in 1941. That day set in motion major changes to counterterrorism policies and practices, as well as changes throughout the intelligence community. Those events propelled the U.S. into two major wars and led to the establishment of the U.S. Department of Homeland Security (DHS) and the implementation of extensive surveillance measures nationwide. Undoubtedly, 9/11 permanently altered daily routines. In many ways, it also reshaped how people think of conflict, personal safety, and the safety of others. 

Although the U.S. has not experienced a similar scale attack since policymakers and national security experts debate the probability of such a tragedy happening again on U.S. soil. More than two decades later, many Americans question, “Are we any safer?” particularly with events as recent as September 2024 when a “would-be” terrorist was arrested in Canada and accused of planning a mass shooting at a Jewish center in New York City in support of the Islamic State terror organization. The scale was aspirational, but the ongoing heightened threat to national security remains. 

Terrorist Threats Across Decades 

Four years before al-Qa’ida operatives attacked the World Trade Center and the Pentagon in 2001, then-Central Intelligence Agency (CIA) Director George Tenet testified publicly several times about the existential threat al-Qa’ida posed to U.S. interests domestically and abroad. Tenet said, “the system was blinking red.” According to the 9/11 Commission, at the beginning of 2001, officials were receiving frequent reports about threats that appeared to be emerging from almost everywhere the U.S. had interests. Despite those intelligence concerns, Americans view terrorism as a less critical threat than they did following the 9/11 attacks. According to research, in 2002, roughly 9 out of 10 Americans viewed terrorism as a critical threat versus only 6 out of 10 Americans in 2022. Americans’ concern about international terrorism has declined considerably in recent years. 

Fast-forward decades later, Federal Bureau of Investigation (FBI) Director Christopher Wray testified before Congress that the terrorism environment is quite “elevated” and further “heightened” following the Hamas attack on Israel on October 7, 2023. The FBI believes that the danger of an Islamic extremist-inspired terrorist attack inside the U.S. is at the highest point since 9/11. Director Wray, testifying at the annual “Worldwide Threats” congressional hearings in March 2024, stated that: 

Even before the October 7th attacks, I would have told this committee that we were at a heightened threat level from a terrorism perspective – in the sense that it’s the first time I’ve seen in a long, long time, the threats from homegrown violent extremists that is jihadist-inspired extremists, domestic violent extremists, foreign terrorist organizations, and state-sponsored terrorist organizations all being elevated at one time since October 7, though, that threat has gone to a whole other level. And so, this is a time I think for much greater vigilance, maybe been called upon us. 

One area of current major concern is the ongoing threat of the homegrown violent extremist in the U.S. Although not “official” members of terror organizations, these individuals are typically the lone actors who merely draw inspiration from the actions of both domestic and foreign terrorist movements. In Director Wray’s testimony before the Judiciary Committee in December 2023, he stressed that the greatest threat to the U.S. stemmed from homegrown violent extremists, citing that the homegrown violent extremist “is the greatest, most immediate international terrorism threat to the homeland.” 

The October 2023 Hamas attack and Israel’s military response have increased tensions regionally and abroad, particularly with the continued media coverage of the destruction in Gaza and the loss of life that localized social media campaigns amplify. In turn, new narratives are created in neighboring countries and beyond. Israel’s military response in Gaza and Lebanon coupled with the support from the U.S. could generate a breeding ground for the next generation of terrorists. Israel says it wants to destroy Hamas and its supporters like Hezbollah, but military operations alone (like those Israel has implemented in Gaza and Lebanon) cannot prevent radicalization. In retrospect, the world witnessed this with the creation of another terror movement following the 2003 U.S.-led invasion of Iraq, which ultimately produced the Islamic State terror organization.  

In 1997, the U.S. State Department listed Hamas as a designated terrorist organization that seeks to destroy Israel but has also been historically rooted in international political Islam and participated in elections, resulting in strong global influence in the Islamic community. The collateral damage created from the Gaza conflict could likely become the best recruitment tool for Hamas or far worse, from another terror group the world has not yet seen. The current projections will increase the risk to Israel and the U.S. through mass radicalization. As with prior conflicts in the Middle East, the recent fighting in Gaza and Lebanon will likely trigger terrorist consequences elsewhere in the region. At the annual hearing on global security threats, Director of National Intelligence Avril Haines stated, “The crisis [in Gaza] has galvanized violence by a range of actors around the world. And while it is too early to tell, it is likely that the Gaza conflict will have a generational impact on terrorism.”  

Mass Radicalization Efforts 

The explosion of social media presents an extraordinary view into mass radicalization. Social media makes it possible for a story [good or bad] to spread in real time. People are now interacting on platforms without knowing one another personally. However, these virtual communities with extremist messaging or created narratives can promote and foster a mobilization of hundreds or thousands of individuals under a common ideology, an injustice, or a grievance. The underlying political message of the idealist battle is apparent in the following examples: 

• The number of attacks on U.S. military bases overseas by Iran-backed militia groups have risen; 

• Cyberattacks against the U.S. by Iran and non-state actors have risen; and 

• There are ongoing plots against the U.S., including the Canadian who attempted to enter the U.S. to carry out a mass shooting at a Jewish Center in New York City. 

According to FBI Director Wray, “since October 7, we’re working around the clock to identify and disrupt potential attacks by those inspired by Hamas’s horrific terrorist attacks in Israel.” 

Aside from Hamas, the U.S. must remain vigilant with the ongoing threat of Islamic State. The 2024 Annual U.S. Intelligence Assessment reported that the regional affiliates of Islamic State and al-Qa’ida are likely to expand in the future and, although terrorism capabilities will fluctuate across Islamic State’s factions, the group will continue to focus on conducting and inspiring global attacks against the U.S. and U.S. interests. The report further indicated that al-Qa’ida and Islamic State, have been motivated by the Hamas attack against Israel, and thus directed their own followers to carry out attacks against Israeli and U.S. interests. 

An outpouring of confidence by the global supporters of the Islamic State movement has become apparent. Online threats against the European community coupled with the successful coordinated attack in Russia on a concert venue foster a potential shift in U.S. thinking about the possible reach of Islamic State. The U.S. intelligence community has elevated concern, especially after attacks against Taylor Swift concerts in Vienna, Austria, were thwarted in August 2024. Individuals tied to Islamic State made preparatory actions to attack concert venues holding up to 65,000 people inside and potentially thousands more congregating outside the stadium. 

In June 2024, the House Committee on Homeland Security reported that over 370 individuals on the terrorist watchlist had been caught trying to cross the Southwest border since 2021. FBI Director Wray previously stated in March that dangerous individuals have entered the U.S. illegally at the southern border. In summer 2024, a coordinated sting operation spanning Los Angeles, New York, and Philadelphia arrested several individuals with suspected terror ties to Islamic State who crossed the border illegally. Wray commented following the arrest that, 

[T]he bigger problem, in my view, is twofold. One, individuals who, when they come in, are either armed with fake documents or snuck in some way or – or, and this is very important, individuals for whom there’s not enough derogatory information in the intelligence community to watch list them yet. 

In June 2024, DHS identified and labeled over 400 immigrants who entered the U.S. from Central Asia as “subjects of concern.” Adding to the concern for an Islamic State-inspired attack, those immigrants were brought in by an Islamic State-affiliated human-smuggling network. The law enforcement community must consider the porous border vulnerabilities that foreign terrorist organizations could exploit as an incentive to carry out terrorist attacks. Additionally, porous and uncontrolled borders continue to allow transnational criminal syndicates and violent extremist groups to capitalize on the trafficking and smuggling of humans, narcotics, and weapons. 

With its primary responsibility of preventing people from entering the U.S. illegally, DHS’s Customs and Border Protection must be able to conduct its operations according to the law without political interference. Promoting seamless information sharing across the intelligence community and law enforcement agency platforms facilitates a successful streamlined process that can aid in border security. This process integrates information systems to enable information sharing at the federal, state, and local levels. Such integration would improve information sharing and safeguard processes and capabilities while strengthening intelligence integration and making it seamless among those in place to protect U.S. citizens. 

Heightened Concerns in Afghanistan and the U.S. 

According to the Secretary of Homeland Security Alejandro Mayorkas, speaking before the Committee on Homeland Security, foreign terrorist groups like al-Qa’ida and Islamic State are rebuilding overseas and maintaining worldwide networks of supporters that could target the U.S. The United Nations Security Council released a detailed report in July 2024 highlighting the threats posed by Islamic State and al-Qa’ida, particularly the “heightened” concerns about the “terrorist threat emanating regionally from Afghanistan.” The report suggests that the most serious threat in the region projecting terror beyond Afghanistan and al-Qa’ida’s enduring presence in the country remains a concern as well. The report further indicates that al-Qa’ida members travel through Afghanistan for “training, recruitment and reorganization activities…. [C]ontinued reorganization and training are judged indicative of the group’s longer-term intent.” Moreover, the report includes the following details that raise concern about al-Qa’ida: 

• An ongoing relationship with the Taliban continues to harbor al-Qa’ida members; 

• Al-Qa’ida established nine new terrorist camps in Afghanistan in 2024; 

• Al-Qa’ida leader Saif al-Adl June 2024 requested that foreign fighters travel to Afghanistan and prepare to attack the West; and 

• The current infrastructure and solidified haven in Afghanistan offer opportunities to benefit from al-Adl’s call for supporters to migrate to the country. 

In addition to external forces looking to infiltrate or inspire, cases of domestic terrorism are on the rise in the U.S. According to DHS reports, there were over 231 domestic terrorism incidents in 2010-2021, with roughly 35% classified as racially or ethnically motivated. Anti-government or anti-authority-motivated violent extremism was the second largest category of incidents at 32%. A 2022 FBI report found that racially or ethnically motivated violent extremists will continue to create the highest threat of executing “lethal violence against [U.S.] civilians,” followed by animal rights and environmental violence, which poses a lesser threat. With individuals inspired, for example, by terror movements and violent public demonstrations, policymakers need comprehensive and objective data to better understand the threats, the factors causing increased threats, and recommendations for change. 

According to the Center for Strategic and International Studies, aside from understanding the threats, law enforcement agencies (state, local, and tribal) need further funding and resource assistance to help identify and respond to domestic terrorism before an attack occurs: 

The DHS, DOJ, and FBI should continue to review their respective counterterrorism training and resource programs that are provided to federal, state, local, and tribal law enforcement agencies and ensure that such programs include sufficient training and resources in understanding, detecting, deterring, and investigating acts of domestic terrorism. 

Understanding the Internet’s critical role in terrorism, the U.S. and the private sector should pursue groups or individuals that use internet platforms to advocate for violence. Extremists use the internet to raise money, recruit new members, push propaganda, coordinate training, and communicate with one another. Policymakers should continue to require platforms to aggressively take down subjective content that supports terrorism and potentially fosters radicalization. There has been a continuing problem in government action. By the time a trend is identified, and countermeasures are implemented, that trend has likely decreased and is now replaced by a newer threat profile.