"Properly" is the key word here. Touching my children physically is improper in that it violates their rights and mine. The person who violates their right to be secure in their persons will find out what the penalty for that is.
Putting them in timeout or detention halls is a worthless punishment.
That is your opinion, and it might even be true in whatever crappy schools your children attend. You have a right to send them where ever you choose.
Spanking worked at home and in schools for decades.
Spanking at home is not the topic of this thread. Physical violation by government employees is. This thread isn't even about private education.
Liberals and liberaltarians don't understand the concept that strong punishment deters inappropriate or illegal behavior.
I can't speak for either of the two groups you mention (off topic in any case) but I understand, and the person who physically violates my children will quickly learn the concept that strong punishment will be in store for them.
Children are always testing the limits of acceptable behavior. They, on a deep non-conscious level, want and desire limits... the feeling that someone is watching and guiding them with loving care.
Kids respond to different things, so I'm not a "beat them all" guy. But if sweet reason isn't working and the kid knows that the worst thing that will happen is an ineffectual note back to dithering, hand-wringing parents, then the teachers lose all authority with that kid. There's been a few in my fiancee's classroom that the best she could hope for is if they just slept through class.