Chapter 21: Understanding and Investigating Terrorism
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Chapter 21
Understanding and Investigating Terrorism
Learning Objectives
1. Identify the three radical movements within Islam.
2. Provide a brief history of Osama bin Laden and the evolution of the al-Qaeda terrorist
organization.
6. Describe the prominent national structures involved in terrorist intelligence and outline
their responsibilities.
7. List and explain several ways terrorist organizations finance themselves.
8. List and describe some of the steps every police agency and/or officer can take to prevent
terrorism in the United States.
Introduction
The events of September 11, 2001, were clearly the most horrendous and devastating terrorist
acts ever to occur on U.S. soil. Few people would take issue with the proposition that 9/11
forever changed the lives of all Americans. The events of that day evoked a sense of national
outrage, caused profound losses, and created a sense of vulnerability.
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domestic groups. Right-wing terror groups, along with extremist groups, are responsible for
high-profile incidents in the past, such as the Oklahoma City bombing in 1995, the Charleston,
SC church shooting in 2015, and the attempted kidnapping and murder of Michigan Governor
Although federal agencies are clearly important in assessing the threat of future terrorist acts, the
role of criminal investigators at both the state and the local law enforcement levels should not be
underestimated. The remainder of the chapter outlines the ways that criminal investigators can
assist in the fight against terrorism. Confronting terrorism is not an occasional or a seasonal
venture; it is an ongoing responsibility. Now, more than ever, criminal investigators must be
prepared to encounter and handle terrorist-incident crime scenes.
The world and the United States are not strangers to terrorism. The first U.S. plane hijacking
occurred in 1961, when Puerto Rican Antuilo Ortiz, armed with a gun, diverted a National
plots of violence against airliners in London, the horrible destruction of 9/11, and the gruesome
beheadings of innocent civilians by the Shiite al-Mahdi Army in Iraq. Today, the violence
continues, with apparently random shootings and bombings aimed at mass carnage and
destruction of people worldwide. For example, the National Counterterrorism Center indicates
that over 11,700 terrorist attacks occurred throughout the world in 2015. Although the number of
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Lecture Notes
I. International Terrorism
“International terrorism involves violent acts or acts dangerous to human life that are the
violation of the criminal laws of the United States or any state, or that would be a criminal act if
committed within the jurisdiction of the United States or any state.”
A. Radical Islam
Radical Islam has long been a component of terrorist activity throughout the world. Radical
Islamic groups are generally characterized by a belief that is not shared by mainstream
Wahhabism is an Islamic orientation owing much of its basic ideology to the writings of Abd
al-Wahhab (1703–1792), who espoused a very conservative form of Sunni Islam. The basic
The Muslim Brotherhood movement was formed in 1928 as an Egyptian youth organization
and grew into a political party by 1939, influenced by the writings of Hasan al-Banna (1906–
1949) and Sayyid Qutb (1906–1966) in Egypt. The term jihad is interpreted as an obligation
for all Muslims to engage in a “holy war” against the West.
Shi’a or Shiite are Followers of the Shi’a tradition, often called the “Shi’at Ali” or Party of
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Ali, believe that Ali (the son-in-law of the Prophet Muhammad) was given a divine right of
successorship to lead the Muslim community after the seventh century. Shi’a population is
B. Radical Islamic Groups
Radical Islamic groups and their history, goals, leaders, tactics, and operational methods were
for the most part unknown to state and local investigators before 9/11. Although there are
several Islamic terrorist organizations that are active, the following groups pose the most
• Hezbollah
Although most people associate the birth of the Islamic State (IS) or the Islamic State in
Iraq and Syria (ISIS) with the war in Northern Iraq in 2014, the actual beginnings of the
organization come at least a decade earlier in Middle East history. Abu Musab al-Zarqawi
Many of the radical Sunni fighters loyal to al-Qaeda (like al-Zarqawi) had suffered dramatic
losses to U.S. forces during the Iraq War. Coupled with the loss of political power and, most
In July 2014, the leader of ISIS, Abu Bakr al-Baghdadi, declared himself “caliph” over the
area he controlled and announced the establishment of the new “caliphate.” He then changed
the name of the group to the Islamic State, and within a month (August 2014), he led attacks
on Kurdish territories in northern Iraq, prompting an immediate response by the United
States—retaliatory air strikes and bombing of IS-held areas. He called upon all Muslims
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Al-Qaeda (“the base”) has its basis in the mujahedin, or “holy warriors,” who fought against
the Russians when they invaded Afghanistan in 1979. Osama bin Laden had set up the
organization known as “the base,” or al-Qaeda, in order to track the movements of fighters
and money coming into the Afghan resistance. In 1998 al-Qaeda made its first strike against
the United States.
Hezbollah or “the Party of God” was founded in 1982 in reaction to the Israeli invasion of
Lebanon. The roots of Hezbollah go back to the late 1970s, when hundreds of Shiite clerics
In 2004 Hezbollah won nearly a quarter of the parliamentary seats in the Lebanese
government and was largely responsible for starting the Second Lebanon War in July 2006 by
firing rockets into northern border towns of Israel and capturing several IDF soldiers.
II. Homegrown Terrorism
Homegrown terrorists include those who plot to carry out attacks at home in the United States
and those who provide material support to foreign terrorist organizations via financial,
intellectual, or other means.
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A. Who is the Homegrown Terrorist?
The majority of homegrown terrorists are American citizens, although others may be
immigrants to this country. American citizens are particularly attractive recruits for a couple
B. Attacks from inside the United States
Unfortunately, there have been a number of homegrown terrorists identified in the past few
years. What follows are examples of some of these homegrown terrorists, their motivations,
and their modus operandi in assisting jihadist organizations within the last decade.
• In 2009 Major Nidal Malik Hasan, a psychiatrist for the U.S. army, killed 13 people and
wounded 30 at Fort Hood, Texas, in a processing center for soldiers about to be
• The Boston Marathon bombing on April 15, 2013, marked the first time that radical
Islamic terrorists struck at an American sports event or venue.
• In Chattanooga, Tennessee on July 16, 2015, Mohammad Youssuf Abdulazeez shot five
C. The Changing Nature of the Threat
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In 2017, 2018, and 2019, the number of homegrown terrorist incidents in the United States
has actually reduced as attacks stemming from far-right and hate extremists have dramatically
III. Domestic Terrorism
As defined by the FBI, domestic terrorism is the unlawful use, or threatened use, of violence by
a group or an individual based and operating entirely within the United States or its territories,
without foreign direction, committed against persons or property to intimidate or coerce a
government, the civilian population, or any segment thereof, in furtherance of political or social
objectives.
A. Right-Wing Terrorists
Domestic right-wing terrorist groups often adhere to the principles of racial supremacy and
embrace antigovernment, antiregulatory beliefs. More traditional right-wing groups have
“Sovereign citizens” are right-wing extremists who believe that they get to choose which laws
to obey and are independent of the rule of courts, law enforcement, the IRS, juries, and
elected officials. Nativist movements are also on the rise. Nativists are extremist immigration
opponents who go beyond advocating immigration policy and actually harass or confront
immigrants.
B. Hate Crime
Hate crimes are harms inflicted on a victim by an offender whose motivation derives
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primarily from hatred directed at a perceived characteristic of the victim (e.g., the person’s
race, religion, ethnicity, gender, and/or sexual orientation). These crimes are particularly
C. Left-Wing Terrorists
Left-wing terrorists generally profess a revolutionary socialist doctrine and view themselves
as protectors of the people against the “dehumanizing effects” of capitalism and imperialism.
With the death of George Floyd (and others) at the hands of the police in 2020 and the
The FBI defines ecoterrorism as the use, or threatened use, of violence of a criminal nature
against innocent victims or property by an environmentally oriented, national group for
IV. Financing Terrorist Organizations
A. New Laws and Legal Tools
In the United States, a number of initiatives were created to help combat the financing of
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international financial system.
B. Drug Smuggling
Although the illegal drug trade has been around for centuries, recently much attention has
C. Arms Smuggling
Trades of weapons for commodities, such as drugs that can profitably be sold, are also part of
D. Credit Card Fraud and Theft
Although no exact figure is available on the amount of money terrorists acquire each year
E. Charities Fraud and Linkages
During the past 20 years alone, several groups (including HAMAS, Hezbollah, the Palestinian
Islamic Jihad, al-Qaeda, and ISIS) have used a variety of charities, educational think tanks,
F. Other Criminal Activities Linked to Terrorist Groups
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In addition to the major types of terrorist financing already mentioned, there are many smaller
operations that raise funds. Some of these include selling baby formula on the black market
V. Counterterrorism Intelligence Structures: Fusion Centers and the National
Counterterrorism Center (NCTC)
Following the 9/11 attacks, a major national movement aimed at integrating all information and
intelligence about terrorist groups and potential plans began to take shape. The overarching
process of managing the flow of information and intelligence across all levels and sectors of
government and private security was the impetus to create fusion centers inside local and state
police agencies.
There are two types of fusion centers:
• Primary Fusion Centers: A primary fusion center typically provides information sharing
The goals of a fusion center are fourfold:
• Fusion centers support the broad range of activities undertaken by a police department
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A. Fusion Centers and the National Counterterrorism Center (NCTC)
The National Fusion Center Association (NFCA) is a formal group that represents the
interest of state and local urban area fusion centers nationally. The goal of the NFCA is to
B. Department of Homeland Security
The creation of the Department of Homeland Security represents one of the largest federal
reorganizations since the modern Defense Department was developed in 1947. Created in
C. Investigation of Terrorist Activities
While the role of state and local agencies in combating domestic and international
terrorism is rapidly evolving, there are several steps that police agencies and their officers
can take immediately to thwart attacks:
• Participate in joint terrorism task forces. Joint terrorism task forces (JTTFs) are
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possibility, keep a separate log of suspicious activities.
• Use critical thinking. Critical thinking involves rigorously challenging your own views
and those of others. “Challenging” does not mean being verbally confrontational at
every encounter; rather, it means reasonably assessing the basis of assumptions and
beliefs.
• Be alert for reconnaissance operations. The execution of an attack is predated by
VI. Terrorist Crime Scenes
It is beyond the scope of this section to cover crime scene safety issues for every type of terrorist
A. Limited Biological Attacks: Anthrax
Biological agents include both living microorganisms and the toxins produced by organisms.
Their effect on humans ranges from various degrees of illness to death. Compared with
chemical agents, biological agents are generally slower-acting.
Intestinal anthrax is contracted by eating anthrax-contaminated meat that has been
insufficiently cooked; it produces an acute inflammation of the intestines. Inhalation anthrax
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In the past, workers have died from handling unopened mail containing inhalation anthrax, so
new precautions have been implemented to reduce the potential for receiving anthrax-tainted
mail through the U.S. Post Office and other major carriers.
However, even at a biological scene with no overt dissemination—such as one in which
suspicious mail is unopened, the situation is well controlled, and there is no known
dissemination of a biological agent—precautions are warranted:
• If individuals at the scene are not symptomatic—which is the most likely scenario—
A somewhat higher level of personal protection equipment (PPE) is required at a biological
scene with limited dissemination—such as one in which dissemination occurs only through an
opened letter or package—even if the situation is still fairly contained:
• A full-face-piece respirator, giving facial coverage roughly from the hairline to the chin,
B. Chemical Attacks: Mass Casualties
Chemical attacks may be accomplished with V agents, mustard gas, sarin, soman, and tabun.
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There may or may not be a warning before the attack; people must be on the alert for signs of
danger when they patrol or are assigned to the scene of a possible chemical threat or to a
chemical attack scene. Watch for the following signs of chemical attacks:
• Lack of insects.
The following are some measures to protect people from chemical attack:
• The most important thing an individual can do is resist the urge to rush in and help.
VII. Terrorism and the Future
In addition to the dangers already discussed, other types of terrorist acts are possible, including
agroterrorism, threats to water supplies, and the use of high-energy radio frequency (HERF) and
electromagnetic pulse (EMP) weapons. Agroterrorism is the deliberate and malicious use of