The establishment of the Office of Strategic Services (OSS) during World War II marked one of the most consequential turning points in American military and intelligence history. It was formally created on 13 June 1942 by directive of President Franklin D. Roosevelt, at the urging of World War I hero William J. “Wild Bill” Donovan. Before its formation, the United States had no centralized intelligence or covert action capability. Various parts of the military, the State Department, and the FBI all handled intelligence in an uncoordinated, piecemeal fashion. But Donovan, having observed the British intelligence model firsthand, understood that modern war required more a unified organization capable of gathering intelligence, conducting sabotage, waging psychological warfare, and supporting resistance movements behind enemy lines.
What the OSS became was nothing short of revolutionary. It organized espionage operations deep in occupied Europe, helped train and arm partisan forces, and ran guerrilla campaigns in Southeast Asia and beyond. By the end of World War II, OSS officers were conducting operations from the jungles of Burma to the streets of Paris. Though the OSS was dissolved after the war in 1945, its influence did not fade. Instead, it was institutionalized in two powerful successors that exist to this day, the CIA and the U.S. Army Special Forces.
The CIA inherited the OSS global network of human intelligence collection along with its culture of audacity and decentralized decision making. The early CIA was essentially staffed with former OSS officers who understood that success in covert work often depends on adaptability, improvisation, and seizing fleeting opportunities on the ground. These are lessons that still define CIA operations today, working in contested regions around the world.
Meanwhile, the U.S. Army Special Forces, formally activated in 1952, carried forward the OSS commitment to unconventional warfare. The OSS Operational Groups (OGs) and Jedburgh teams had worked behind enemy lines to train and fight alongside indigenous resistance forces, particularly in France and Southeast Asia. These small, highly trained units formed the template for the modern Green Berets, whose central mission is to work by, with, and through local partner forces. Colonel Aaron Bank, one of the founding figures of Army Special Forces, was himself an OSS veteran who brought the ethos and hard won lessons of behind the lines warfare into the Green Berets’ doctrine and training.
From these roots emerged several core lessons that still guide both intelligence and special operations today. First, the importance of empowering the individual operator cannot be overstated. OSS agents were selected not just for their technical skills, but for their ingenuity, self-reliance, and decisiveness under pressure. That philosophy lives on in the training of both CIA officers and Special Forces soldiers today. These operatives are often tasked with missions that require them to navigate political complexity, cultural nuance, and operational uncertainty without waiting for detailed instructions from Washington.
Second, the OSS demonstrated that irregular warfare is not just a tactical tool, it’s a strategic capability. By working with resistance groups to undermine Axis powers during World War II, OSS operations helped tie down enemy forces, disrupt logistics, and create chaos behind enemy lines. The principle that unconventional forces can help shape the strategic environment has been proven repeatedly since then, from Vietnam to Afghanistan and Syria.
Third, the OSS exposed the need for interagency coordination. During the war, OSS teams frequently encountered bureaucratic infighting with the State Department, the military, and Allied intelligence services. Those challenges were partially addressed by postwar reforms, but even today, success in modern operations requires seamless collaboration between intelligence agencies, military commands, diplomats, and policymakers. While much progress has been made, the underlying lesson from the OSS era remains clear that unity of effort is the difference between operational success and failure.
Perhaps the most enduring contribution of the OSS was its pioneering of indigenous partnership warfare. OSS missions thrived when they empowered local fighters with training, leadership, and support. This approach continues to serve as the backbone of Special Forces missions today, particularly in places where U.S. forces act by supporting local forces rather than fighting alone. Whether training Kurdish forces in Syria or local military in the Philippines, the OSS model of empowering locals is alive and well.
As we pivot into an era of renewed near-peer competition, these lessons are essential. Unlike the more visible military campaigns of the Global War on Terrorism, great power competition will largely be fought in the shadows. Global competitors engage in forms of irregular warfare, including information operations, economic coercion, influence campaigns, cyber intrusions, proxy warfare, methods that don’t require tanks and bombers but instead require intelligence, deception, and influence. For the United States to remain competitive in this arena, they will need to return to those OSS roots, leaning heavily on the capabilities of both the CIA and Special Forces, while evolving their methods for a digitally connected, globally contested environment.
The future will require renewed investment in cultural expertise, language proficiency, and covert influence operations. It will demand a deep understanding of local dynamics in places that are on the periphery of global power contests but pivotal to influence. And perhaps most importantly, it will require the United States to be comfortable once again with operating in ambiguous gray zones where victories are incremental, influence is contested, clear cut outcomes are rare, and tactical decision making with strategic consequences is decentralized.
The OSS legacy is blueprint. As the strategic competition intensifies, the ethos that “Wild Bill” Donovan established of a commitment to daring, adaptability, and unconventional solutions, will be more critical than ever. The next generation of American intelligence officers and special operators would be wise to look back at the OSS not just with nostalgia, but with strategic intent.