This is irony.
It is irony because war is anything but kind. Alliteration would be if both words started with the same letter. Style is not a device, and a simile is when you compare something to something.
Answer:
to make the countries future
Not an oxymoron, because that is when you juxtapose 2 opposites. "Stupid genius"
Not onomatopoeia, because that is using the sound something makes to describe it. "buzz of a bee"
Not analogy, because that us a comparison between two things to explain. "an orange is like a mango, just different"
A refrain is the repetition of certain lines, like a chorus.
