The Molotov cocktail, also known as the booze bomb, alcohol bomb or Molotov bomb, is a generic name used for a variety of improvised incendiary weapons. Simple to make, they are frequently used by rioters.
In action the fuse is lit and the bottle hurled at a target such as a vehicle or fortification. When the bottle smashes on impact, the ensuing cloud of petrol droplets and vapor is ignited, causing an immediate fireball followed by a raging fire as the remainder of the fuel is consumed.
Other flammable liquids such as wood alcohol and turpentine have been used in place of petrol. Thickening agents such as tar, sugar, animal blood, XPS foam, egg whites, motor oil, rubber cement, and washing-up liquid have been added to the fuel, analogously to the use of napalm, to help the burning liquid adhere to the target and create clouds of thick choking smoke.
During World War II, when Finland refused to surrender some strategic ports to the Soviet Union, the Soviets invaded in November 1939, after the Shelling of Mainila. The Finnish Army, facing Red Army tanks in what came to be known as the Winter War, borrowed an improvised incendiary device design from the 1936–1939 Spanish Civil War. In that conflict, General Francisco Franco ordered Spanish Nationalists to use the weapon against Soviet T-26 tanks supporting the Spanish Republicans in a failed 1936 Soviet assault near Toledo, 30 km from Madrid.
When Soviet People's Commissar for Foreign Affairs Vyacheslav Molotov claimed in radio broadcasts that the Soviet Union was not dropping bombs but rather delivering food to the starving Finns, the Finns started to call the air bombs Molotov bread baskets. Soon they responded by attacking advancing tanks with "Molotov cocktails". At first, the term was used to describe only the burning mixture itself, but in practical use the term was soon applied to the combination of both the bottle and its contents. This Finnish use of the hand- or sling-thrown explosive against Soviet tanks was repeated in the subsequent Continuation War. Molotov cocktails were eventually mass-produced by the Alko corporation at its Rajamäki distillery, bundled with matches to light them. Production totalled 450,000 during the Winter War. The original design of Molotov cocktail was a mixture of ethanol, tar and gasoline in a 750 ml bottle. The bottle had two long pyrotechnic storm matches attached to either side. Before use one or both of the matches was lit; when the bottle broke on impact, the mixture ignited. The storm matches were found to be safer to use than a burning rag on the mouth of the bottle.
They also saw use during the Nomonhan Incident, a border conflict ostensibly between Mongolia and Manchukuo that saw heavy fighting between Japanese and Soviet forces. Short of anti-tank equipment, Japanese infantry attacked Soviet tanks with gasoline-filled bottles. Japanese infantrymen claimed that several hundred Soviet tanks had been destroyed through the use of Molotov cocktails, though Soviet loss records do not support this assessment.
The Polish home army developed a version which ignited on impact thus avoiding the need to light the fuse before throwing. Ignition was caused by a reaction between concentrated sulfuric acid mixed with the fuel and a mixture of potassium chlorate and sugar which was crystalized from solution onto a rag attached to the bottle.
It should be noted while Molotov cocktails may be a psychologically effective method of disabling tanks and armored vehicles by forcing the crew out or damaging external components, most modern tanks cannot be physically destroyed by Molotov cocktails, only disabled. Tanks and IFVs have specially designed Nuclear, Biological and Chemical protective systems that make them internally air-tight and sealed; well protected from vapors, gases, and liquids. Modern tanks possess very thick Composite Armour consisting of layers of steel, ceramics, plastics and Kevlar, which would make them extremely difficult to destroy by Molotov cocktails alone, as these materials have melting points well above the burning temperature of gasoline. Damaging external components such as optical systems, antennas, or externally-mounted weapons systems is however possible and can make a tank virtually "blind", forcing the crew to at least open the hatches and access ports for the crew, which would allow further measures to be taken against the crew. The burning mixture is effective against tanks' radiators. If the incendiary liquid is thick yet viscous, it can effectively penetrate a tank's radiator cover and overheat the engine's cooling mechanism.
In France, there were also rumors during the closing days of the Paris Commune in 1871 of lower-class women known as pétroleuses, who reportedly committed arson against private property and public buildings by throwing bottles full of petroleum or paraffin into cellars. Though the story was later disproved and is believed to have been anti-Commune propaganda, it was still widely believed until the 20th century.