Napalm

Napalm is a specific type of incendiary mixture designed to burn intensely. An incendiary is a substance used to start or spread fires. To create napalm, chemists combine a gelling agent with a volatile petrochemical, such as gasoline or diesel fuel. The term "napalm" is actually a portmanteau, which is a word made by joining parts of two other words. It comes from the names of its original thickening agents: naphthenic acid and palmitic acid. This mixture is much more effective for certain tasks than plain gasoline. While gasoline creates a brief, blooming fireball, napalm can be projected in a solid, coherent stream. This allows it to travel much longer distances through the air.

The mechanism of napalm relies on its unique physical properties. Because the gelling agent thickens the fuel, the substance becomes extremely sticky. When it is ignited, it adheres to whatever surface it touches. This allows the fire to stay in one place and burn for a longer duration than liquid fuel. Napalm also has the ability to flow into difficult spaces. It can move into foxholes, tunnels, bunkers, and even irrigation ditches. Once inside these shelters, the substance continues to burn. Some versions of the mix even included phosphorus to help the fuel penetrate deeply into organic material.

The development of napalm was driven by a shortage of natural resources during World War II. In the early 1940s, the Allied forces used jellied gasoline, but they relied on latex to create these mixtures. Natural rubber became very scarce after the Japanese army captured rubber plantations in Malaya, Indonesia, Vietnam, and Thailand. This shortage forced scientists at companies like DuPont and Standard Oil, along with researchers at Harvard University, to find alternatives. A team of chemists led by Louis Fieser worked in a secret laboratory at Harvard to develop a synthetic version. By April 1942, they had created a brown, dry powder. This powder was not sticky on its own, but it turned into a highly flammable gel when mixed with gasoline. The first official test occurred on July 4, 1942, near Harvard's Ohiri Field.

Napalm saw widespread military use throughout the twentieth century. Its first combat use was in August 1943 during the Allied invasion of Sicily. During World War II, two-thirds of all napalm bombs were used in the Pacific War. These were often used against fortifications on islands like Saipan, Iwo Jima, and Okinawa. A 1946 report from the National Defense Research Council stated that 40,000 tons of M69 napalm bombs were dropped on Japan. This caused damage to 64 cities and resulted in more deaths than the atomic bombings of Hiroshima and Nagasaki. The substance was also used during the Korean War to provide close air support for ground troops.

The Vietnam War marked a period of intense and heavy use of napalm. Between 1963 and 1973, the United States dropped approximately 388,000 short tons of napalm bombs in the region. The military used it against many different targets, including tanks, buildings, and even railroad tunnels. Beyond the physical destruction, the substance had a psychological effect on both soldiers and civilians. It was deployed from various platforms, including aircraft, tanks, ships, and infantry flamethrowers. One example of this was the use of "Zippo" riverboats in the Navy.

Because of its intense heat and chemical nature, napalm is extremely dangerous to living things. It causes severe burns upon contact. When the mixture burns, it undergoes a process called deoxygenation, which means it removes oxygen from the surrounding air. This can lead to asphyxiation, which is the inability to breathe, or carbon monoxide poisoning. Even people in undamaged shelters can suffer from hyperthermia, which is an extreme rise in body temperature, or smoke exposure. The intense heat is so strong that it can even be conducted through the metal armor of fighting vehicles.

The use of napalm has led to significant changes in international law. While international law does not specifically ban incendiary weapons against military targets, it does protect civilian populations. In 1980, the United Nations adopted Protocol III of the Convention on Certain Conventional Weapons. This protocol bans the use of incendiary weapons against civilians. As of December 1983, this became part of international law, and 126 countries have ratified it. In modern military operations, the United States has largely replaced napalm with the Mark 77 bomb.