Napalm, a thickened gasoline first developed during World War II, rapidly became one of the most infamous incendiary weapons of the modern era. Its sticky, highly flammable qualities made it devastatingly effective on the battlefield yet equally controversial in the court of public opinion. Thefirst use of napalm in combatoccurred on 17 July 1944, during the Allied push across Normandy in the weeks following DDay. On that day, American P38 Lightning fighterbombers dropped newly developed napalm canisters on a German fuel depot near the French town of SaintLô. Although this initial deployment was limited in scope, it signaled a dramatic shift in aerial bombardment tactics and foreshadowed the weapon’s much wider use in later conflicts. Understanding the circumstances of napalm’s first use its scientific origins, strategic purpose, battlefield impact, and ethical implications offers valuable insight into the evolving nature of warfare in the twentieth century.
Scientific Origins of Napalm
Development at Harvard University
The story of napalm began far from the front lines, in a chemistry laboratory at Harvard University. In early 1942, chemist Louis Fieser and his research team were commissioned by the United States Office of Scientific Research and Development to create a more reliable incendiary agent than existing jellied gasoline formulas. Their breakthrough came with the discovery that mixing naphthenic and palmitic acids hence the name napalm with gasoline produced a thick, sticky gel capable of burning intensely and adhering to surfaces.
Advantages Over Conventional Incendiaries
- Consistency: Napalm’s gelled texture prevented rapid evaporation, making storage and transport safer.
- Adhesion: The sticky substance clung to buildings, vehicles, and sometimes personnel, ensuring longer burn times.
- Ignitability: When dispersed from bombs or flamethrowers, napalm ignited easily and maintained high temperatures.
These properties impressed military planners seeking to destroy fortified positions, supply depots, and dense urban targets more effectively than with highexplosive ordnance alone.
Strategic Context in Summer 1944
The Normandy Campaign
Following the 6 June 1944 landings in Normandy, Allied forces faced fierce German resistance in the hedgerow country of northern France. The German army relied on scattered fuel depots and ammunition dumps to keep frontline units supplied. Disrupting these logistical hubs became a priority for the Allied air forces, which were eager to test new weapons capable of destroying strategic reserves quickly.
Choosing Napalm for the Mission
By midJuly 1944, sufficient stocks of napalm canisters were available for operational testing. Commanders identified a German fuel storage site near SaintLô, an area of intense fighting where Allied ground troops were preparing a breakout offensive. Targeting a fuel depot made sense: it was relatively isolated, and the flammable contents would amplify the incendiary effect, allowing analysts to gauge napalm’s destructive potential.
The First Combat Deployment
Aircraft and Ordnance
On 17 July 1944, a formation of Lockheed P38 Lightnings from the U.S. Ninth Air Force took off with 500pound M69 napalm canisters strapped beneath their wings. Each canister contained a mixture of gasoline thickened with the Harvard gel, along with a small bursting charge to disperse the burning gel upon impact.
Attack on the SaintLô Fuel Depot
Pilots approached the target at low altitude to improve accuracy. Upon release, the canisters ruptured and scattered blazing streams of jellied gasoline across the depot. The resulting firestorm ignited fuel drums, storage tanks, and nearby structures. Within minutes, towering flames and black smoke columns marked the site’s destruction. Reconnaissance reports later confirmed the depot was completely gutted, with secondary explosions indicating widespread ignition of stored fuel.
Tactical and Operational Impact
Results on the Ground
- The German fuel shortage in the sector increased, limiting armored counterattacks during the Allied breakout.
- Allied planners recognized napalm’s capacity to create largescale fires quickly, making it useful against similar softtarget installations.
- The successful mission bolstered confidence in napalm’s utility and led to expanded production for both European and Pacific theaters.
Learning Curve for Pilots
Although the mission succeeded, pilots noted challenges in delivery accuracy and the risk of flying low over enemy territory. Subsequent tactics evolved, with bomber aircraft such as the B25 Mitchell and the Douglas A20 Havoc employed to carry larger loads from higher altitudes, balancing precision and crew safety.
Expansion of Napalm Use
European Theater
After SaintLô, napalm was used in the bombing of Germanheld cities like Brest and Le Havre and against entrenched positions in the Siegfried Line. The rapid spread of fire in urban environments demonstrated napalm’s effectiveness in disabling enemy morale and infrastructure.
Pacific Theater
Perhaps the most notorious World War II deployment of napalm occurred in the Pacific, where U.S. Army Air Forces used it extensively during the islandhopping campaign. Napalm strikes on Saipan, Iwo Jima, and Okinawa burned through jungle foliage, caves, and defensive tunnels. Most notably, the firebombing of Japanese cities including the devastating Tokyo raid of 910 March 1945 relied heavily on napalm clusters dropped from B29 Superfortresses, leading to massive civilian casualties.
Ethical Controversies and Public Perception
Humanitarian Concerns
From its earliest use, napalm raised moral questions. Its ability to adhere to skin and burn at temperatures exceeding 800 °C meant horrific injuries for victims. Civilian areas in occupied Europe and Japan, often near military targets, faced the risk of uncontrollable fires.
Legacy in Later Conflicts
Napalm’s reputation further darkened during the Korean and Vietnam Wars, where iconic images such as the 1972 photograph of a burned Vietnamese girl galvanized global protest movements. The 1980 United Nations Convention on Certain Conventional Weapons later restricted the use of incendiary weapons against civilian populations, although major powers have not fully eliminated napalm from their arsenals.
Scientific and Military Legacy
Refinements in Incendiary Technology
Post1944, chemists refined napalm formulations to improve storage stability and reduce accidental ignition. Newer variants like NapalmB (also known as super napalm) incorporated polystyrene and benzene, producing an even thicker fuel that burned longer and hotter.
Doctrinal Shifts
Air forces integrated napalm into combinedarms doctrines:
- Suppression of Enemy Defenses: Napalm preceded infantry assaults on bunkers and trenches, forcing defenders into the open.
- Area Denial: Largescale fires impeded enemy movement through forests and urban corridors.
- Psychological Warfare: The fearsome effects of napalm could lower enemy morale and induce surrender.
The first use of napalm near SaintLô on 17 July 1944 marked a watershed in the evolution of modern warfare. In a single mission, Allied forces demonstrated the strategic potential of a weapon that combined chemistry, aeronautics, and tactical innovation. While militarily successful, napalm introduced a new dimension of horror that quickly became emblematic of the ethical dilemmas posed by incendiary weapons. From the hedgerows of Normandy to the jungles of Southeast Asia, napalm’s legacy is one of both battlefield effectiveness and profound humanitarian controversy. Understanding its initial deployment helps illuminate the complex interplay between technological advancement, military necessity, and moral responsibility in armed conflict.