Ever since the end of the Cold War, there has been an assumption that conventional warfare between reasonably developed nation-states had been abolished. During the 1990s, it was expected that the primary purpose of the military would be operations other than war, such as peacekeeping, disaster relief and the change of oppressive regimes. After 9/11, many began speaking of asymmetric warfare and “the long war.” Under this model, the United States would be engaged in counterterrorism activities in a broad area of the Islamic world for a very long time. Peer-to-peer conflict seemed obsolete.
There was a profoundly radical idea embedded in this line of thought. Wars between nations or dynastic powers had been a constant condition in Europe, and the rest of the world had been no less violent. Every century had had systemic wars in which the entire international system (increasingly dominated by Europe since the 16th century) had participated. In the 20th century, there were the two World Wars, in the 19th century the Napoleonic Wars, in the 18th century the Seven Years’ War, and in the 17th century the Thirty Years’ War.
Those who argued that U.S. defense policy had to shift its focus away from peer-to-peer and systemic conflict were in effect arguing that the world had entered a new era in which what had been previously commonplace would now be rare or nonexistent. What warfare there was would not involve nations but subnational groups and would not be systemic. The radical nature of this argument was rarely recognized by those who made it, and the evolving American defense policy that followed this reasoning was rarely seen as inappropriate. If the United States was going to be involved primarily in counterterrorism operations in the Islamic world for the next 50 years, we obviously needed a very different military than the one we had.
There were two reasons for this argument. Military planners are always obsessed with the war they are fighting. It is only human to see the immediate task as a permanent task. During the Cold War, it was impossible for anyone to imagine how it would end. During World War I, it was obvious that static warfare dominated by the defense was the new permanent model. That generals always fight the last war must be amended to say that generals always believe the war they are fighting is the permanent war. It is, after all, the war that was the culmination of their careers, and imagining other wars when they are fighting this one, and indeed will not be fighting future ones, appeared frivolous.
The second reason was that no nation-state was in a position to challenge the United States militarily. After the Cold War ended, the United States was in a singularly powerful position. The United States remains in a powerful position, but over time, other nations will increase their power, form alliances and coalitions and challenge the United States. No matter how benign a leading power is — and the United States is not uniquely benign — other nations will fear it, resent it or want to shame it for its behavior. The idea that other nation-states will not challenge the United States seemed plausible for the past 20 years, but the fact is that nations will pursue interests that are opposed to American interest and by definition, pose a peer-to-peer challenge. The United States is potentially overwhelmingly powerful, but that does not make it omnipotent.
Systemic vs. Asymmetric War
It must also be remembered that asymmetric warfare and operations other than war always existed between and during peer-to-peer wars and systemic wars. The British fought an asymmetric war in both Ireland and North America in the context of a peer-to-peer war with France. Germany fought an asymmetric war in Yugoslavia at the same time it fought a systemic war from 1939-1945. The United States fought asymmetric wars in the Philippines, Nicaragua, Haiti and other places between 1900-1945.
Asymmetric wars and operations other than war are far more common than peer-to-peer and systemic wars. They can appear overwhelmingly important at the time. But just as the defeat of Britain by the Americans did not destroy British power, the outcomes of asymmetric wars rarely define long-term national power and hardly ever define the international system. Asymmetric warfare is not a new style of war; it is a permanent dimension of warfare. Peer-to-peer and systemic wars are also constant features but are far less frequent. They are also far more important. For Britain, the outcome of the Napoleonic Wars was much more important than the outcome of the American Revolution. For the United States, the outcome of World Was II was far more important than its intervention in Haiti. There are a lot more asymmetric wars, but a defeat does not shift national power. If you lose a systemic war, the outcome can be catastrophic.
A military force can be shaped to fight frequent, less important engagements or rare but critical wars — ideally, it should be able to do both. But in military planning, not all wars are equally important. The war that defines power and the international system can have irreversible and catastrophic results. Asymmetric wars can cause problems and casualties, but that is a lesser mission. Military leaders and defense officials, obsessed with the moment, must bear in mind that the war currently being fought may be little remembered, the peace that is currently at hand is rarely permanent, and harboring the belief that any type of warfare has become obsolete is likely to be in error.
Ukraine drove this lesson home. There will be no war between the United States and Russia over Ukraine. The United States does not have interests there that justify a war, and neither country is in a position militarily to fight a war. The Americans are not deployed for war, and the Russians are not ready to fight the United States.
But the events in Ukraine point to some realities. First, the power of countries shifts, and the Russians had substantially increased their military capabilities since the 1990s. Second, the divergent interests between the two countries, which seemed to disappear in the 1990s, re-emerged. Third, this episode will cause each side to reconsider its military strategy and capabilities, and future crises might well lead to conventional war, nuclear weapons notwithstanding. Ukraine reminds us that peer-to-peer conflict is not inconceivable, and that a strategy and defense policy built on the assumption has little basis in reality. The human condition did not transform itself because of an interregnum in which the United States could not be challenged; the last two decades are an exception to the rule of global affairs defined by war.
U.S. national strategy must be founded on the control of the sea. The oceans protect the United States from everything but terrorism and nuclear missiles. The greatest challenge to U.S. control of the sea is hostile fleets. The best way to defeat hostile fleets is to prevent them from being built. The best way to do that is to maintain the balance of power in Eurasia. The ideal path for this is