IIRC the US did plan in case either Japan or Germany somehow became capable of bombing the states. Some factories had their roofs painted to make them blend in

IIRC the US did plan in case either Japan or Germany somehow became capable of bombing the states. Some factories had their roofs painted to make them blend in with the surroundings, others were built out of reinforced concrete to make them bomb proof https://airmail.news/arts-intel/highlights/masters-of-disguise-1253 https://airmail.news/arts-intel/highlights/masters-of-disgui...