ITA. I have smacked before. Especially Chase who likes to do stupid things like burn his hands on the oven and end up in emergency, pull the oil heater on himself, run into the middle of the bus mall and almost get hit by a bus on the kurb. In those situations he has got a smack because I can not risk him doing them again (well not the burning himself thing but when he went to touch hot again I smacked and said no HOT)
However these occasions are rare, not daily or weekly or even monthly. I can't remember the last time I smacked.
We use the corner here with great effect. Even when we are out, if they are naughty they get a warning that if they don't stop it will be the corner and usually we don't get to that stage. However, if we do, they go face a wall or corner somewhere. Believe it or not we don't get ANY remarks from passers by as you would if you smacked.
Firstly sounds like you stopped your behaviour out of fear of getting a smack, not because you knew the behaviour was bad. I think it is cruel to tell them when they get home they will get a smack. It is making them spend the whole time out worrying about what will happen when they get home. I know this because I have had many discussions with my mum who was always told "when your father gets home he will deal with you" and she would worry ALL day. (usually for no reason because he would either say not to worry or yell a bit)
Secondly it is illegal to smack a child with anything OTHER than your hand, so a object SHOULDN'T be used. You are only allowed to smack below the waist and you are not allowed to leave any marks.

