National Terrorism Advisory System

Bulletin www.dhs.gov/advisories November 9, 2017 1:00PM EST 

SUMMARY OF TERRORISM THREAT TO THE U.S. HOMELAND

Since 2015, the Department of Homeland Security (DHS) has used this Bulletin to highlight the continuing terror threat to the 

U.S. Homeland. The United States is engaged in a generational fight against terrorists who seek to attack the American 

people, our country, and our way of life. An informed, vigilant and engaged public remains one of our greatest assets to 

identify potential terrorists and prevent attacks.

DURATION

This Bulletin 

will expire on 

May 9, 2018 

at 1:00PM EDT

ADDITIONAL DETAILS

• We continue to face one of the most challenging threat environments since 9/11, as foreign terrorist organizations 

exploit the Internet to inspire, enable, or direct individuals already here in the homeland to commit terrorist acts. 

Homegrown terror suspects increasingly rely on technology, such as end-to-end encrypted social media applications, 

to avoid detection.

• Terrorist groups are urging recruits to adopt easy-to-use tools to target public places and events. Specific attack tactics 

have included the use of vehicle ramming, small arms, straight-edged blades or knives, homemade explosives, and 

poisons or toxins.

• Some terrorist groups overseas are using battlefield experiences to pursue new technologies and tactics, such as 

unmanned aerial systems and chemical agents that could be used outside the conflict zones. Additionally, terrorists 

continue to target commercial aviation and air cargo, including with concealed explosives. 

• Violent extremist media encourages individuals worldwide to launch attacks using all means possible. Continued U.S. 

and partner successes in disrupting and defeating terrorists on the battlefield may encourage homegrown terrorists to 

carry out acts of violence in the homeland instead of attempting to travel overseas to fight or in retaliation for apparent 

losses. 

• Additionally, foreign terrorist fighters who have acquired training and battle-tested terrorism experience may flee from 

terrorist-controlled territories with a desire to conduct attacks elsewhere, including the United States.

U.S. GOVERNMENT COUNTERTERRORISM EFFORTS

• DHS and the Federal Bureau of Investigation (FBI) continue to provide guidance to state, local, tribal and territorial 

partners related to the current threat environment. DHS also partners closely with the private sector to provide risk 

assessments and coordinate security measures with business owners and operators. The public may continue to observe

law enforcement and security activity in and around public places and events.

• DHS protects the homeland from terrorism by working closely with the FBI and other intelligence partners to 

detect and disrupt terror suspects, putting in place additional screening and vetting measures to identify 

suspicious travelers and cargo, combating violent radicalization and terrorist recruitment in our communities,

monitoring emerging threats, and engaging with foreign partners. 

• More broadly, DHS remains committed to preventing violence and threats meant to intimidate or coerce specific

populations on the basis of their religion, ethnicity or identity.

TYPES OF 

ADVISORIES

Bulletin

Describes current 

developments or 

general trends 

regarding threats 

of terrorism.

Elevated Alert

Warns of a 

credible terrorism 

threat against the 

United States.

Imminent Alert

Warns of a 

credible, specific 

and impending 

terrorism threat 

against the United 

States. 

HOW YOU CAN HELP

• Report suspicious activity to local law 

enforcement who can best offer specific 

details on terroristic indicators.

• Report suspicious activity or information 

about a threat, including online activity, 

to fusion centers and the FBI’s Field 

Offices – part of the Nationwide 

Suspicious Activity Reporting Initiative. 

• Learn how to recognize signs of preoperational planning associated with 

terrorism or other criminal activity.

BE PREPARED

• Be prepared for security and plan ahead. 

Anticipate delays and restrictions on items 

around populated places and at public 

events.

• Be responsible for your personal safety. 

Know where emergency exits and security 

personnel are located. Carry emergency 

contact and special needs info with you. 

• Connect, Plan, Train, and Report to prepare 

businesses & employees. Security 

tools/resources can be accessed through 

the DHS Hometown Security Campaign. 

STAY INFORMED

• The U.S. Government will provide additional 

information about any emerging threat as 

additional information is identified. The public 

is encouraged to listen to local law

enforcement and public safety officials.

• We urge Americans to continue to travel, 

attend public events, and freely associate 

with others but remain vigilant and aware of 

surroundings.

• The Department of State issues 

international travel alerts and warnings.

• Fo

 

r additional information visit Ready. 

If You See Something, Say SomethingTM. Report suspicious activity to local law enforcement or call 911.

The National Terrorism Advisory System provides information on homeland security issues and threats. It is distributed by the Department of Homeland 

Security. More information is available at: www.dhs.gov/advisories. To receive mobile updates: www.twitter.com/dhsgov 

If You See Something Say SomethingTM used with permission of the NY Metropolitan Transportation Authority.