Well, they have implemented such measures in the west because the physique of westerners is huge. one slap can easily land a kid in the hospital, if not the morgue!
ok, 'nuff kidding. the reason parents discipline their kids is so that they grow up as good citizens. you don't need a law to tell when a parent's spanking turns abusive. no amount of law can stop parents from abusing their kids. and no law can tell a parent that it is wrong to slap a kid if the parent is trying to discipline his/her kid.
for those who quote western standards, here's an example. i was at kmart, and a kid was pestering her mom to buy her some candy. the mom was in no mood to relent. the kid slipped the candy in her pocket (the equivalent of shop lifting) and displayed her steal after her mom had passed the checkout counter. her mom gave her a glare, and when that didn't wipe the kid's smile, she gave a nice whooping on her backside in full view of everybody who cared to see. with tears running down her eyes, the kid returned the candy at the same spot she had picked it from. everybody saw the incident and no one thought of calling 911. no prizes for guessing why - the mom was simply teaching the kid what was right and what was wrong.
a parent spanks his/her kid so that he/she learns the right stuff. so that a couple of years down the line the 'junta' doesn't have to spank (figuratively speaking) him/her in full view/knowledge of the parent.
