Sorry- about to ruin the lighthearted tone and probably kill the thread!
I think there are worse things than smacking as described here by custy and bloss and others, I really do. But I'm not sure if I buy the argument that kids are fundamentally different from adults and that it's therefore okay to treat them differently, if necessary utilising punishments such as smacking and shouting in a good cause. Of course children need lots of guidance from parents and other adults, and clear messages and rules about how to keep safe and behave appropriately in various situations, together with knowledge that there will be consequences if they choose to disobey. I also agree that it's utterly ludicrous to pretend that kids and their parents have equal power. We don't- I'm in charge in my house because I'm the adult. And yes, I have an agenda- I want them to learn to be safe, behave as well as they can, learn about the way the world works to the best of their abilities, reflect well on their ace parents etc etc. I enforce the rules to this end. I have the power and my babies know it. They aren't thick- they know that they are little, need looking after and that they are thus at the mercy of the big mamma and dadda they've drawn in the parent lottery.
But is that so different from our lives as adults? Power hierarchies are a fact of adult life too- there are rules, there are bosses, there are people in charge. And there are also ways of using power respectfully that most people agree on. If my boss hit me when I failed to do my monthly monitoring forms I would be furious. If my housing officer had screamed at me because I was in rent arrears a few years ago I would probably have ended up evicted because I'd have been too upset to find a solution to the problem. I don't think either my boss or my housing officer would go down these routes for a moment. But that's not to say that I think it's ok to neglect (a hated) part of my job or not to pay my rent- I know that these people have power over me, I know what the rules are, I understand why the rules are there, I know there are consequences if I decide to break them. I also feel that my boss wants me to succeed at work and do the best job I can- both so that our organisation is providing a good service and because she cares about my professional development (or at least puts on a good act!). I believe that my housing officer doesn't want to put me and my family out on the street. But if these people had chosen to deliver their unwanted but necessary messages of doom via smacks and yelling, I have to say I might well have started doubting their basic benevolence because I would have felt really really shit.
If we as adults have certain reasonable expectations of how those in power should behave towards us, why should children be so different? I think the very least I owe my boys is to be very aware of how I'm using my power. For me that means smacks are off the agenda.