Environmentalists did harm by being ignorant and ideological and unwilling to change their mind based on actual evidence. As a result we have done harm and I regret it.

环保人士的无知和理想主义，及不愿意基于事实证据改变其想法的行为造成了伤害。对我们所做出的伤害，我感到很后悔。

youdao

I regret what I've done.

我为我所做的一切感到抱歉。

youdao

I have no regret for whatever I have done.

我对我所做的绝不后悔。

youdao