Jail is unpleasent and I do not wish to go there

At what point did we decide corporal punishment less humane than imprisonment?  Let's take a look at some problems with jail:

• Prison rape.  If we're not willing to administer the punishment ourselves, we shouldn't let prisoners do it to each other
• Prison non-sexual assault:  ditto.  Plus, both of these things disproportionately hit the weakest people, who disproportionately commit the more modest crimes.  That's a terrible incentive system.
• Prison entrenches certain long term bad behaviors- people join gang for protection and are obligated to them after they leave.  They make fun new criminal contacts with which to commit future crimes.  The social skills they learn are based on an atmosphere of fear and survival of the meanest.  They learn nothing about running their own life in a productive manner.
• Reintegrating after a prison term of any length is almost impossible.  This makes it much easier to slide back in to criminal behavior
• It's ineffective. People apply <a href="http://en.wikipedia.org/wiki/Discount_rate">discount rates</a> to their time the same way they do to their money.  So you reach diminishing returns with how big a disincentive you can create with a longer sentence.  Worse, the disincentive attenuates faster the worse the person is at planning for the future- which criminals/potential criminals disproportionately are, almost by definition.  But even though each month provides less disincentive than the last, it's just as expensive, and just as destructive to the person's long term prospects.
• Even the crappy job we currently do at running prisons is expensive as hell.

Whereas caning... hurts.  And then is over.  And we can move the money we save from punishment into enforcement, greatly increasing the sureness of punishment  Put another way:   Right now your chances of being caught at an individual robbery are basically 0.  If you do enough there's a chance you might eventually get caught, but it's not likely.  So no matter how big the penalty is, stupid 16 year olds who have seen their friends steal stuff and suffer no consequences are going to steal.  You could make the punishment 100 years in jail and it won't matter.    On the other hand, imagine if every time you stole something, a policeman immediately appeared behind you, whacked you on the ass, took away the stuff you stole, and walked away.  You would stop stealing because there would be no point.  We're never going to reach that level of swiftness/sureness for a lot of reasons, but I think moving towards that end of the spectrum would be beneficial.

Or course, a large part of how jail lowers the crime rate is by rendering the criminals busy.  But if that's what we want to do, we should admit it, rather than pretend it's a punishment.  And we could still have a 10-strikes-and-you're out law  (or a 10 strikes and you're in jail till you're 40 law.  Their lives are ruined, but people don't commit many crimes after 40, it's a lot of work and testosterone is no longer making them stupid) .  

The constitution says no cruel or unusual punishment.  I sincerely don't understand how taking away a month of my life is less cruel than caning, and I really, really don't see how it's less cruel than where that month of life would go in the system as practiced now- rape, torture, and mental deprivation.

Alternate solution:  make all prison solitary confinement, and make the sentences much much shorter.  That at least deals with the things prisoners do to each other and some of the cost.