Answer:
personification
personification in the sentence -
a poem in which a tree is said to walk and talk like an old man uses the technique of personification.
Explanation:
This poem refers to the real-word issue of the genocide of the Jewish population in Europe during Second World War, and specifically to the systematic extermination in the death camps, where people got tatoos with numbers upon their arrival
It broadens its view to consider the service people around the world.