Furui giron o kurikaeshite mo nō wa nai no da yo.Repeating old arguments isn't of any use / won't have any effect.

Kōgeki wa muda datta.The attack was in vain.

jijitsu ni terashite…in light of the facts…

Kedo sā, yoku kangaete mitara kimoku ne?But when you think about it though, isn't it kinda disgusting?