https://en.wikipedia.org/wiki/Bat_bomb

He believed that if time-release incendiaries could be attached to bats, some kind of container holding them could be dropped over the city after dark and the bats would simply roost and burn Tokyo to the ground.[5] The plan was subsequently approved by President Roosevelt[6] on the advice of Donald Griffin.[7] In his letter, Adams stated that the bat was the “lowest form of animal life”, and that, until now, “reasons for its creation have remained unexplained”.[4]: 6  He went on to espouse that bats were created “by God to await this hour to play their part in the scheme of free human existence, and to frustrate any attempt of those who dare desecrate our way of life.”[4]: 6  Of Adams, Roosevelt remarked, “This man is not a nut. It sounds like a perfectly wild idea but is worth looking into.”[2][3]

It gets worse after that. Mercifully, they don’t really go into the details in the article, which mainly involved the bats either still being hibernating or else with the bomb part too heavy, basically they were just dropping innocent bats out of planes to splat onto the ground in big numbers like Wile E. Coyote until someone put a stop to it all.