An idiom meaning 'someone else's problem' — treating a harmful or worrying situation as if it doesn't concern you.
災害のニュースを見て『うちは大丈夫』と言うのは対岸の火事だ。
Saying 'we're fine' while watching disaster news is treating it like someone else's problem.
彼は同僚のミスを対岸の火事のように見ているが、チーム全体に影響する可能性がある。
He regards his colleague's mistake as someone else's problem, but it could affect the whole team.
環境問題を対岸の火事だと考えてはいけない。
You shouldn't think of environmental problems as someone else's problem.