Taking a very long view, it quickly becomes apparent that the various troubles that today are labeled as substate threats are not at all new. The ancient world exhibited them all. The Roman Empire—the superpower of its day—contended with insurrections and rebellions. It dealt with lawlessness and absence of authority on its borders. The Romans certainly knew civil war, which led to their own transition from republic to empire. There was terrorism, too, especially religiously inspired terrorism, as indicated by some of the vocabulary we associate with it today. The original Zealots were members of a Jewish millenarian sect that fought against Roman rule in Palestine.2
If we take a not quite so long view, there is no clear trend of increasing substate threats. There probably is no such trend at all. The historian Niall Ferguson offers several explanations, which are grounded in changing economic and political structures, for why in most of the world (but perhaps not the Middle East) the 21st century is unlikely to be as bloody as the 20th century was.3 Interstate wars are a big part of that picture, of course, but so is substate conflict. Much of Ferguson’s analysis, drawing on things such as the degree of ethnic heterogeneity within nation-states, is about the prospect for less substate violence.
The monsters that the United States has searched for and confronted have taken a variety of forms, from single hostile states to whole categories of trouble that constitute much of what today comes under the heading of nonstate threats. There was the Axis of World War II, of course, which was replaced quickly by the Soviet empire. During the four decades of the Cold War, the Soviet Union served so reliably as the arch-threat in the American worldview that monster-searching did not go much beyond looking for Moscow’s hand in mischief and mayhem around the world. The sudden end of the Cold War, which some call World War III, brought a decade of fumbling by pundits for a new threat-defined way of describing the role of the United States. The terrorist event of September 2001 led many of those pundits to believe that way had finally been found, as the administration of George W. Bush declared a global “war on terror.“4
Since then, much discourse about other substate threats has been linked to the more specific issue of terrorism. For some, the United States has been in “World War IV,” a grand struggle against multiple manifestations of Islamic extremism.5 Others, who do not reduce U.S. national security challenges to such simplistic terms, nonetheless tie sundry nonstate difficulties to terrorism in other ways. Insurgents are categorized according to whether or not they are associated with al Qaeda. Internal disorder is looked at worryingly as providing a potential new haven for terrorists. A frequent question asked about criminal organizations is whether they have ties to terrorists. The distinction between countering terrorism and countering the proliferation of certain categories of unconventional weapons gets blurred—or obliterated altogether as Bush did in endeavoring to tie his case for invading Iraq to the “war on terror.“6
The conceptions of nonstate threats embodied in all of that thinking are reflections more of a long-standing American worldview and American habits of conceiving the U.S. role in global affairs than they are of characteristics of the threats themselves. Accordingly, a disconnect exists between how the threats are usually treated in American debate and how much of a danger they actually pose to U.S. interests. The disconnect is most often in the direction of threats being overrated. Understanding that disconnect requires a closer examination of each of the fundamental ways in which substate conflict can endanger U.S. interests. One way is through the overthrow of an incumbent regime, thus leading to the advent of an unfriendly government in its place. A second concerns threats that substate actors can pose more directly, without a change in regime. A third possibility is trouble stemming not from a particular regime or group but instead from internal disorder itself.