Noun / な-Adj + でなくてなんだろう

[If it's not ..., then what is it?]

Connection: Noun / な-Adjective + でなくてなんだろう(か)

Usage: A rhetorical question structure meaning "if this isn't X, then what is?" Used to strongly assert that something is undoubtedly X. Emphasizes that there is no other way to describe the situation. Literary and emphatic.

Variations:

• でなくてなんだろう (standard)
• でなくてなんであろう (more formal)
• でなくてなんだろうか (with question particle)

Examples:

これが奇跡でなくてなんだろう。(If this isn't a miracle, then what is it?)

彼の行為が裏切りでなくてなんだろうか。(If his actions aren't betrayal, then what are they?)

この美しい光景が幸せでなくてなんだろう。(If this beautiful scene isn't happiness, then what is?)