Christopher Clark’s The Sleepwalkers is an important book, not only because it marks the centennial of when the great powers of the day took the world to war but also because it serves as a cautionary tale for the present. The world today is creeping uncomfortably close to the geostrategic chaos that marked the dawn of the 20th century.

By the time Gavrilo Princip pulled out his pistol and assassinated Austrian Archduke Franz Ferdinand, the heir to the Habsburg throne, major continental powers had already made a mess of European security. The system that was set up to keep powerful European nations in check after the Congress of Vienna had sustained a general peace for one year short of a century. The 1815 pact, which was cut between the power brokers of Europe after the final defeat of Napoleon, stated that each would respect the sphere of influence of the other. But it was a deal that couldn’t last. The unification of Germany in the last quarter of the 19th century created a new, powerful player that left the status quo unworkable. Over the following decades, the major European powers tried to maintain a sense of balance through a series of alliances. On the morning of June 28, 1914, that effort unraveled, thus precipitating the crisis that led to conflict.

The title of this book is actually misleading. Clark, a modern history professor at the University of Cambridge, England, demonstrates that the great powers were not asleep at the wheel. They gripped it, white-knuckled, with both hands. Each power feverishly struggled to provide for its own security. They were wide awake when the crash came, but they found avoiding conflict impossibly difficult.

There are a number of strengths to this work. For example, Clark does a masterful job deconstructing how the complex decisionmaking machinery of each of the belligerent nations worked, and how this dissonance greatly complicated the process of avoiding war. Clark’s most valuable contribution, however, is that he wades through a century of scholarship highlighting the key debates, weighing the evidence and interpretations, and delivering his own judgments.

Still, even Clark doesn’t provide convincing answers to all the controversies. His most notable question is whether Germany intentionally engineered preventative war, an interpretation championed by historian Fritz Fischer in the 1960s. Clark alleges that the “Fischer thesis” distorts understanding the outbreak of the war: “[T]he quest for blame predisposes the investigator to construe the actions of decisionmakers as planned and driven by coherent intention.” That is a fair criticism, but it doesn’t completely absolve Berlin. Even though Austria-Hungary, Serbia and Russia mobilized before Germany, the Germans’ decision to go to war ensured the spread of the conflict over whether or not Serbia was responsible for the archduke’s assassination. Germany had only one workable war plan, and it called for taking on both Russia and France—a decision that also dragged Britain into the conflict.

his book is particularly compelling because the insurmountable security challenges Clark describes bear an eerie resemblance to the world in which we live today. If the architecture of future global security rests on a handful of squabbling middle powers—each with its own independent interests, seeking security by carving out its own sphere of safe haven and cutting deals with one another—then should we be any more confident that today’s policymakers will be any more effective at managing such a complex and messy world? In some ways, the problems today are even more acute than they were in 1914. The world is a lot better at killing today than it was a century ago. A conflict on the scale of 1914 may very well slaughter billions today, as opposed to the millions who died during the last century’s prolonged conflict.

Perhaps the greatest lesson to be learned from World War I is that people should not want to live in that kind of world. Since World War II, U.S. military power has been adequate enough to deter global conflict, keep regional conflicts from spinning out of control, and ensure the relative freedom of the commons in sea and space. If the U.S. military’s power continues to decline, this safety net will be lost. Alliances may shift and mark out their own regional spheres of influence, as they did in the early 20th century. That world may be too difficult for mere mortals to manage. Odds are, there will be fewer of the “sleepwalkers” Clark writes about and more leaders with sleepless nights in the potentially dangerous days ahead.

 - Lt. Col. James Jay Carafano, USA Ret., Ph.D., served in Europe, Korea and the United States. Before retiring, he was the executive editor of Joint Forces Quarterly, DoD’s professional military journal. A graduate of the U.S. Military Academy, Carafano holds a master’s degree and a doctorate from Georgetown University as well as a master’s degree in strategy from the U.S. Army War College.