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:I’m tall when I’m young, and I’m short when I’m old. What am I?
Explanation:
It determines how much information the reader has access to.
There are two verbs- started and running
The verb phrase is- started running