Federal authorities have issued a bulletin warning that foreign terrorist organizations continue to encourage attacks within the United States, with specific concern over the use of 9/11-related propaganda in advance of previous anniversaries. The bulletin, reviewed by ABC News, highlights the FBI's apprehension that individuals in the U.S. may be inspired to commit violence or engage in hoax threats, particularly as the 25th anniversary of the 9/11 attacks approaches.

This warning comes amid an evolving and increasingly complex terrorism threat environment. Unlike the pre-9/11 era, where the primary concern stemmed from centralized international organizations, the current landscape is described as broader and more dispersed. While established groups like ISIS and al-Qaeda remain a threat, individuals and small cells are now plotting attacks independently, often driven by a diverse range of ideological and political motivations.

The bulletin indicates that messaging from foreign terrorist organizations, combined with ongoing conflicts in the Middle East, could exacerbate existing grievances against the United States and potentially lead to mobilization for violence. Officials noted that actors have demonstrated a willingness to act with minimal or no prior warning, adding a layer of urgency to the advisory.

The Department of Homeland Security (DHS) has acknowledged the heightened threat, stating that the environment has significantly changed since the 2001 attacks. A DHS spokesperson elaborated that these groups are not only seeking to carry out attacks but also to inspire them. Furthermore, domestic terrorists, often motivated by anti-government sentiments and a desire to destabilize society, continue to plan acts of violence within the U.S.

In the past year and a half, the FBI has reportedly arrested at least 16 individuals within the United States for allegedly plotting or supporting attacks on behalf of al-Qaeda or ISIS. This underscores the ongoing efforts of these organizations to influence and direct actions within American borders.

A March report from the U.S. intelligence community indicated that while ISIS and al-Qaeda may be increasingly relying on social media to reach Americans, their overseas membership is growing. ISIS is estimated to have up to 18,000 members globally, while al-Qaeda's ranks could reach as high as 28,000.

The DHS, established in the wake of the 9/11 attacks to consolidate homeland security agencies, also flagged concerns about terrorists experimenting with artificial intelligence. This includes using generative AI to create and disseminate propaganda and exploring methods for employing explosives and biological agents.

These evolving tactics and the continued encouragement of violence by foreign terrorist groups, coupled with the rise of domestically motivated threats, present a persistent challenge to national security agencies as they prepare for the upcoming anniversary.