Terrorism Defined and Why It Matters
J. Robert Kane
The Islamic State of Iraq and the Levant (ISIL) is the most rapidly advancing terrorist group of the past five years.  The problem is that it is not a terrorist group at all.
Just because a group commits grave atrocities and “terrorizes” citizen populations does not make it a terrorist group. That is not what terrorism means.
Because ISIL advances to control territory and holds land at times, it is disqualified from being termed a terrorist group according to the US Government (USG). Terrorist groups do not hold land. 
By the USG definition according to Title 22 Chapter 38 U.S. Code § 2656f, terrorism is defined as "premeditated, politically motivated violence perpetrated against noncombatant targets by subnational groups or clandestine agents." This is also the definition that is used by USG agencies in order to define acts of terrorism. More definitions may exist in other sectors but this is the most precise way to define terrorism.
This means that terrorism is violence against noncombatants (namely civilians) in order to achieve political objectives. Terrorist groups do not hold land or territory because terrorism is a form of political violence or ideology as opposed to any sort of legitimate colonial power or state. Maintaining land is not an objective of terrorism and would demarcate the group in question to a definition of something else.
The latter part of the official USG definition is not that important in combatting terrorism aside from terrorism being committed by non-governmental entities. Government agents themselves do not employ terrorism. Despite this, terrorism can be employed as a form of state-craft as seen in the cases of Iran’s use of Hezbollah and Libya (under Gadhafi) establishing terrorist training camps on Libyan soil, providing terrorists with arms, and offering safe haven to terrorist groups under attack of the U.S. 
As a form of achieving larger political objectives, terrorism works. It is highly effective especially when forces that aim to combat it are ineffective. If combatting terrorism is unimpeded by national power, the political aims are often satisfied. When it comes to solving solutions to political problems that are not possible within the larger, legitimate political process, terrorism is the method of choice. 
While counterterrorism strategies have become more adept at countering the threat over the past decade, terrorism was previously often met with little resistance. The U.S. claims to no longer negotiate with terrorists although we know that is not really the case.  Because terrorism possesses larger ideological factors that cannot be easily dismantled, terrorists hold the power to negotiate. History would tell us that negotiation works.  The same is not true for insurgents.
In contrast to terrorism, an insurgency is defined according to the U.S. Department of Defense as “an organized movement aimed at the overthrow of a constituted government through use of subversion and armed conflict.” This is not the only definition of an insurgency but it is the most succinct and operationally important. Other definitions may consider more considerations such as moral questions but that is not very important to understanding what an insurgency is. Hence, this is the definition most of the USG uses.
That means that ISIL is an insurgency. While some can argue that it is merely semantics, it is not. This differentiation is important because how you combat terrorism or an insurgency is different and correctly identifying one or the other will determine the strategy used.
Meanwhile, al-Qaeda has been discounted as of late despite posing a more serious threat to U.S. interests than ISIL ever has. It has gone underground at times or had distinct branches form from its initial group such as al-Qaeda in Iraq (AQI) or al-Qaeda in the Arabian Peninsula (AQAP), but its focus has not lessened. The motivations of al-Qaeda have not diminished and that is why the group remains the single largest target of U.S. airstrikes. But that also gets to why definitions manner. 
al-Qaeda does satisfy the definition of a terrorist group. It is a non-governmental group. It uses violence to achieve political means. It does not hold land. And it operates according to an ideology that is different from a temporal objective or end state.
How we combat al-Qaeda as a terrorist group as opposed to the insurgency that is ISIL is very different. The strategies that are used may often appear similar or even the same at times (and that is a mistake). But the difference is that insurgencies aim to achieve immediate objectives while terrorism possesses an ideology that reflects a desire to achieve larger political aims according to what is believed. For the future, the strategy for combatting each of these two groups needs to be further delineated to reflect the differences in what sort of operations can be conducted in order to combat them.
One of the more important reasons for U.S. success in combatting ISIL is the fact that very kinetic operations (drone strikes, direct action, etc.) tend to be more effective in eradicating insurgencies as opposed to terrorism. Kinetic operations have been unprecedented against ISIL such that insurgents can be literally removed from a geographic area, liberating the area of operations from insurgent control. The literal removal (death) of insurgents from the geographic area also means that the insurgents are no longer able to operate the insurgency. The insurgency does not possess the same generational value as does terrorism.
Counterinsurgency (COIN) theory dictates that non-kinetic operations are key to combatting insurgencies. Forces that take part in the counterinsurgency must conduct stability operations in order to maintain effective measures against the insurgency. General David Petraeus made this clear during his tenure in Afghanistan and I would agree. Winning the hearts and minds of the local populace is imperative to winning the fight against an insurgency. But that is in the context of winning the support of the locals in order to allow them to feel secure and in synchronization with the forces combatting the insurgency. It manifests itself in a stability operation in preparation of kinetic operations against the insurgency and afterwards to prohibit the insurgency from support. 
But kinetic actions against the insurgency is the only way to defeat it. Stability operations in the form of non-kinetic operations ensure that the insurgency remains fixed and unable to re-surface.
Kinetic operations against al-Qaeda have also been very frequent. The immediate results of kinetic operations against al-Qaeda targets is effective in the short-term but as we know, the long-term effects of kinetic operations against terrorist groups tend to be counterproductive in combatting terrorism.  Kinetic operations make it nearly impossible to conduct more non-kinetic operations that involve understanding and countering the roots of terrorism in the first place—the really essential factors of what will actually make a difference in the fight against terrorism.
The definition is important in this case. It allows for us to understand when and how various kinetic/non-kinetic operations will succeed. Even when dependent on mission-specific factors, the determination as to the operation’s success is highly dependent on these definitions. Many people fail to recognize the difference between terrorism and insurgencies, including some in the USG. But this results in a strategy that is bound to fail because the assessment did not accurately define the problem in the first place.
Arguably, it is this reason why counterterrorist strategies against al-Qaeda do not succeed well in the long-term. It is true that terrorism will never go away but that does not mean that alleviating it is impossible.
Terrorism can be alleviated despite not being capable of being eradicated. But it will take some work and cannot be expected to be an easy task. It will involve more non-kinetic operations than kinetic in support of getting to the heart of terrorism as opposed to just striking it from time to time.
But it first necessitates understanding the definition of terrorism and what it means. Equally as important, it means understanding what it is not.
The views, opinions, and findings of the author expressed in this article should not be construed as asserting or implying U.S. government endorsement of its factual statements and interpretations or representing the official positions of any component of the United States government.
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