Answer:
The poet uses if to indicate that whatever he is referring to does not have to perish twice.
Step-by-step explanation:
By adding if, it signifies this is not actually happening, and it is more of a "what if?" statement. If the sentence was left without it, it would imply that is has to perish twice.
"But it had to perish twice."
See the difference?
Hope this helped!
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