世が世なら死刑だぞ。。
Ifを使ってもいいですが手っ取り早い英語表現があります。
There was a time when SV
世が世ならSはVだ。
例)
There was a time you would have got hung.
世が世なら絞首刑だぞ。
There was a time when he would have been an aristocrat.
世が世なら彼は貴族だぞ。
hang-hung-hung
If these were the good old days,
古き良き時代だったら、
例)
If these were the good old days, we wouldn’t be like this.
古き良き時代なら、俺らはこんなざまじゃないはずだ。