Even though U.S. forces have left Iraq and there is a planned reduction in U.S. forces in Afghanistan, the era of counterinsurgency is far from over. Irregular warfare is the oldest form of warfare—it long predates the rise of conventional armies in ancient Mesopotamia around 3000 BC. Irregular warfare has been ubiquitous throughout history and is more important than ever today, at a time when conventional warfare is growing increasingly rare. America's enemies understand that to fight the U.S. armed forces with conventional forces in the open field is tantamount to suicide—as Saddam Hussein discovered for himself. Irregular-warfare tactics, on the other hand, have shown a far higher likelihood of success against American military forces. Our enemies study, and are inspired by, the examples of Vietnam, Beirut (1983), Somalia (1993), Iraq, Afghanistan and other conflicts where irregular forces have inflicted significant setbacks and even defeats on American forces. Moreover the conditions for the growth of insurgency—chiefly a lack of effective governance—exist in many areas of the world, especially in Central Asia, South Asia, the Middle East, Africa, and parts of Latin America and Southeast Asia. For all these reasons irregular warfare will continue to be prevalent.
"Irregular warfare is far more intellectual than a bayonet charge."
"The shooting side of the business is only 25% of the trouble and other 75% lies in getting the people of the country behind us."
--Field Marshal Sir Gerald Templer
Counterinsurgency is the use of all elements of a nation's power—including not only combined-arms operations but also psychological, political, economic, intelligence, and diplomatic operations—to defeat an insurgency. An insurgency is an organized uprising that uses violent and nonviolent means to overthrow an existing government or to wrest away control, either de jure or de facto, over part of its territory. Insurgencies typically have political or religious motivation but criminal gangs can also become powerful enough to imperil a state's authority. Most insurgencies utilize a combination of guerrilla and terrorist tactics—the former are hit-and-run attacks directed primarily at government security forces, the latter are attacks directed primarily against civilians—supported by propaganda and political organizing.
Successfully countering an insurgency will require commanders to skillfully synchronize multiple lines of operations, acting in concert with host-nation forces as well as representatives of other U.S. government agencies. International organizations, non-governmental organizations, and the news media are also likely to be present on the battlefield, and the successful commander must interact with them constructively, and if possible use them to achieve campaign objectives, even though they are outside the military chain of command.
Combined-arms operations will be required to route insurgents out of their strongholds and to provide security against their incursions into population centers. But, while the aggressive pursuit of insurgent forces is necessary, it is insufficient to achieve victory—and if undertaken in indiscriminate fashion can actually backfire by creating more insurgents than you capture or kill. Insurgents, in fact, count on security forces to over-react and thereby to drive more recruits into their ranks.
The basis of successful counterinsurgency is acquiring intelligence to identify an enemy that often hides in plain sight. Some of that intelligence can be acquired by technical means, but there is no substitute for the situational awareness provided by security forces (whether American or host-nation) who are in daily contact with the population. Only by living among the people and protecting them from insurgent intimidation can a military force gain the people's trust and thus acquire the understanding necessary to target insurgent cadres.
Securing the population is thus the most important line of operations. As John Paul Vann, an American adviser in Vietnam, said, "Security may be ten percent of the problem, or it may be ninety percent, but whatever it is, it's the first ten percent or the first ninety percent. Without security nothing else will last." The security line of operations must be buttressed by attempts to win the trust of the populace and enhance the legitimacy of the counterinsurgents. This does not necessarily mean increasing the capacity of the host-nation government--if the government is widely seen as corrupt or illegitimate, making it more powerful can be self-defeating. Nor does it necessarily involve spending lots of money on expensive public-works projects that the locals may not want and will be unable to operate on their own. It does mean addressing the desire of the people for self-determination and the delivery of some basic governmental services. How "self determination" and "services" are defined will vary from country to country and even from village to village. It is the foremost responsibility of a commander in a COIN environment to understand the unique human and geographical terrain on which the maneuver forces operate.
T.E. Lawrence attributed his success in aiding the Arab Revolt against the Ottoman Empire to "hard study and brain-work and concentration," an example at odds with what he denounced as the "fundamental, crippling, incuriousness" of many fellow officers who were "too much body and too little head." Future combat leaders should heed Lawrence's injunction to study hard, especially when preparing for COIN—the most intellectually challenging realm of warfare.
First, maneuver leaders should become familiar with the relevant Army doctrine, which in turn can provide leaders with a context for studying history. Second, once familiar with relevant doctrine, leaders should read books and articles that provide an overview of irregular warfare operations since ancient times as well as accounts of its evolution since the early 20th century. Next, leaders might study a specific COIN operation in which integration of whole-of-government efforts made possible the defeat or significant diminution of the enemy. Examples include the Philippine Insurrection, the Boer War, the Huk Rebellion, the Malay Emergency, the "Troubles" in Northern Ireland, the 1980s war in El Salvador, the "surge" in Iraq, the Second Intifada, and Colombia's campaign against the FARC in the past decade. Conversely leaders should also look at unsuccessful COIN campaigns to see what mistakes to avoid. Examples include the American Revolution, the Irish War of Independence, Yugoslavia during World War II, the French wars in Indochina and Algeria, the US war in Vietnam, and the Soviet campaign in Afghanistan.