 By the time American B-29 Superfortress bombers reached the Japanese home islands and intensely firebombed industrial and civilian centers with impunity, the leaflets had improved, providing "advance notice" of bombings ensured that the leaflets were read avidly despite prohibitions.These pamphlets were dropped in many targeted Japanese cities, declaring they had no wish to harm civilians but rather only strategic targets such as military bases and defense industries, encouraging them to flee the cities to avoid the bombings, and that the bombings could be stopped by demanding new leaders who would end the war.After the atomic attacks, more pamphlets were dropped, warning that the Americans had an even more powerful explosive at their disposal equal to that of 2,000 B-29 bombers carrying thousands of conventional bombs.