越南戰爭，美軍十年投下38萬8千噸，輕鬆摧毀裝甲車輛、建築物、叢林，鐵路隧道，比白磷彈恐怖萬倍，凝固汽油彈（燒夷彈）

凝固汽油彈（英語：napalm），亦稱燒夷彈，是幾種武器用途的可燃液體之總稱，大多以膠狀汽油為主成份。「napalm」指的是凝固汽油彈中用來與汽油混合以產生膠質燃劑的黏稠劑成份。此詞是由它的研發者路易·菲塞（Louis Frederick Fieser）所領導的哈佛大學化學家團隊所命名，是naphthenic（環烷酸）與palmitic acid（棕櫚酸）的鋁鹽的混成詞，製造凝固汽油彈時會將這兩種成份加入可燃物質使其膠質化。凝固汽油彈早期主要被用來攻擊建築物，之後演變為對人員殺傷用武器，其主要通過黏附在人員表面持續燃燒來造成傷害。
Napalm is an incendiary mixture of a gelling agent and a volatile petrochemical (usually gasoline (petrol) or diesel fuel). The name is a portmanteau of two of the constituents of the original thickening and gelling agents: coprecipitated aluminium salts of naphthenic acid and palmitic acid. Napalm B is the more modern version of napalm (utilizing polystyrene derivatives) and, although distinctly different in its chemical composition, is often referred to simply as "napalm". A team led by chemist Louis Fieser originally developed napalm for the US Chemical Warfare Service in 1942 in a secret laboratory at Harvard University. Of immediate first interest was its viability as an incendiary device to be used in fire bombing campaigns during World War II; its potential to be coherently projected into a solid stream that would carry for distance (instead of the bloomy fireball of pure gasoline) resulted in widespread adoption in infantry flamethrowers as well.