The incredible bacterial 'homing missiles' that scientists want to harness

Imagine there are arrows that are lethal when fired on your enemies yet harmless if they fall on your friends. It's easy to see how these would be an amazing advantage in warfare, if they were real. However, something just like these arrows does indeed exist, and they are used in warfare ... just on a different scale.

source https://phys.org/news/2021-04-incredible-bacterial-homing-missiles-scientists.html