Napalm is a gelatinous substance developed during World War II to be used as fuel for flamethrowers. Although it burned too fast to be an effective weapon, it was later re-engineered at Harvard to use latex from trees to last much longer. Napalm is such an effective weapon because of its ability to not only seep into bunkers and tunnels alike, but also its ability to stick to human skin and continue to burn without any known way to effectively remove it without serious injury. The only way to attempt to remove napalm from a person was to use a cloth to rub it away, which actually just spread it around more to cause even more injury. Wherever napalm is has not seemed into, it can burn all of the air in the vicinity, effectively suffocating any dug-in enemies. Roughly 338,000 tons of napalm were dropped during the Vietnam War.
Psychological and Physical Effects on People
Being an incendiary weapon, napalm is capable of causing severe burns, asphyxiation, unconsciousness, and death. The substance can create fires that have an atmosphere of greater than 20% carbon monoxide which leaves anyone near it to be susceptible to carbon monoxide poisoning, which is definitely lethal. Napalm was also used as a form of psychological warfare due to its effect of large and very, very hot firestorms that leave permanent marks on its victims and leave them in agonizing pain from the literal melting of human cells to the point beyond repair.