Definition of terrorism in the context of "Counterterrorism"

Several national governments and two international organizations have created lists of organizations that they designate as terrorist. The following list of designated terrorist groups lists groups designated as terrorist by current and former national governments, and inter-governmental organizations. Such designations have often had a significant effect on the groups' activities.

Many organizations that have been designated as terrorist have denied using terrorism as a military tactic to achieve their goals, and there is no international consensus on the legal definition of terrorism.

A suicide attack (also known by a wide variety of other names, see below) is a deliberate attack in which the perpetrators intentionally end their own lives as part of the attack. These attacks are a form of murder–suicide that is often associated with terrorism or war. When the attackers are labelled as terrorists, the attacks are sometimes referred to as an act of suicide terrorism. Military use of suicide is not directly regulated by international law, but suicide attacks sometimes violate prohibitions against perfidy or targeting civilians. Suicide attacks have occurred in various contexts, ranging from military campaigns—such as the Japanese kamikaze pilots during World War II (1944–1945)—to more contemporary Islamic terrorist campaigns—including the September 11 attacks in 2001. Suicide attacks have been used by a wide range of political ideologies, from far-right (Japan and Germany in WWII) to far-left (such as the PKK and JRA).

In the United States, a common definition of terrorism is the systematic or threatened use of violence in order to create a general climate of fear to intimidate a population or government and thereby effect political, religious, or ideological change. This article serves as a list and a compilation of acts of terrorism, attempts to commit acts of terrorism, and other such items which pertain to terrorist activities which are engaged in by non-state actors or spies who are acting in the interests of state actors or persons who are acting without the approval of foreign governments within the domestic borders of the United States.

During the American Civil War, pro-Confederate Bushwhackers and pro-Union Jayhawkers in Missouri and Kansas respectively engaged in cross border raids, committed acts of violence against civilians and soldiers, stole goods and burned down farms. The most infamous event occurred in Lawrence, Kansas on August 21, 1863, when Quantrill's Raiders led by William Quantrill ransacked the town and murdered about 190 civilians because of the town's anti-slavery sentiment. Other acts of terrorism occurred during the war included the 1863 Chesapeake Affair and the 1864 St. Albans Raid, the former being committed by British subjects.

Counterterrorism (alternatively spelled: counter-terrorism), also known as anti-terrorism, relates to the practices, military tactics, techniques, and strategies that governments, law enforcement, businesses, and intelligence agencies use to combat or eliminate terrorism and violent extremism.

If an act of terrorism occurs as part of a broader insurgency (and insurgency is included in the definition of terrorism) then counterterrorism may additionally employ counterinsurgency measures. The United States Armed Forces uses the term "foreign internal defense" for programs that support other countries' attempts to suppress insurgency, lawlessness, or subversion, or to reduce the conditions under which threats to national security may develop.

Terrorism in India, according to the Ministry of Home Affairs, poses a significant threat to the people of India. Compared to other countries, India faces a wide range of terror groups. Terrorism found in India includes Islamist terrorism, ultranationalist terrorism, and left-wing terrorism. India is one of the countries most impacted by terrorism.

A common definition of terrorism is the systematic use or threatened use of violence to intimidate a population or government for political, religious, or ideological goals.