You should be able to conceive of the fact that short term suck can pay for long term good.

Yes, of course. Indeed, there are few long term goods that can be purchased without short term suck.

But you weren't arguing that punishing criminals was a long term bad, or even insufficiently good. You were arguing that it was short term suck.

Those words are loaded with connotation. Why are you using them?

Invert the order of the sentences, and you have your answer. But I will answer at length:

The history and law and order is one of long and painful experience. The common law definition of "assault" did not spring forth from first principles, it was learned.

The source of order is deterrence; deterrence rests on expectations; expectations rest on identities. The brute is resisted in a way that the even-handed is not; the infirm are flaunted in a way that the firm are not.

So theres no such thing as extenuating circumstances where we let someone off, but everyone understands that the threat of punishment is still there?

Accepting any excuse reduces the credibility of the commitment. Sometimes you may think that reduction is acceptable, but you should never pretend it was absent.