Firebombing

The Chinese wartime capital of Chongqing was firebombed by the Imperial Japanese starting in early 1939 during the Second Sino-Japanese War.

The result was, of course, that an efficient fire brigade could tackle a single load of incendiaries, put them out, and wait in comfort for the next to come along; they might also be able to take shelter when a few high explosives bombs were dropping.

But it was observed that when the Germans did get an effective concentration, ... then our fire brigades had a hard time; if a rain of incendiaries is mixed with high explosives bombs there is a temptation for the fireman to keep his head down.

The Germans, again and again, missed their chance, as they did during the London blitz that I watched from the roof of the Air Ministry, of setting our cities ablaze by a concentrated attack.

But they did do us enough damage to teach us the principle of concentration, the principle of starting so many fires at the same time that no firefighting services, however efficiently and quickly they were reinforced by the fire brigades of other towns could get them under control.The tactical innovation of the bomber stream was developed by the RAF to overwhelm the German aerial defenses of the Kammhuber Line during World War II to increase the RAF's concentration in time over the target.

But after the lessons learned during the Blitz, the tactic of dropping a high concentration of bombs over the target in the shortest time possible became standard in the RAF as it was more effective than a longer raid.

[8] Changing to low-altitude night tactics to concentrate the fire damage while minimizing the effectiveness of fighter and artillery defenses, the Operation Meetinghouse raid[9] carried out by 279 B-29s raided Tokyo again on the night of 9/10 March, dropped 1,665 tons of incendiaries from altitudes of 5,000 to 9,000 ft (1,500 to 2,700 m), mostly using the 500-pound (230 kg) E-46 cluster bomb which released 38 M-69 oil-based incendiary bombs at an altitude of 2,500 ft (760 m).

[10] The first to arrive dropped bombs in a large X pattern centered in Tokyo's working class district near the docks; later aircraft simply aimed near this flaming X.

Approximately 15.8 square miles (4,090 ha) of the city were destroyed and 100,000 people are estimated to have died in the resulting conflagration, more than the immediate deaths of either the atomic bombings of Hiroshima or Nagasaki.