[He's too tired to keep arguing about all the things he should have done to prevent that threat from looming over them in the first place. The fact is he didn't do them and no amount of whining and self-pity is going to change it.]

You're right... Besides, there's nothing to be done about what has already passed. I can only learn from it and prepare from whatever comes in the future!

[And he's... so worried about what might happen now.]