tough love

What is tough love?  Is that simply a term we adults use to say we get our children to mind but do so in a way that we claim it is for their own good.  Or is it a way for others to judge us and tell us if we truly loved our kids we would intervene.
    You know I'm not sure, but I think it means it's not so much touch on the kids but actually tough on us.  I have watched my now 8 year old and the art of crying for nye on 5 years.  If his brother so much as gets within a foot he can start the tears flowing and make up an excuse that his brother has hit, pinched, or kicked him somewhere - even when not true.  So does a crying toddler in his bed know what he is doing.  Is it conscious or subconscious.  Are they really upset or is crying just a form of communication.  If your 2 year old yells at you to get back in their room right now - would you or would you promptly tell him he may not talk to you that way.
    From the beginning of early infancy crying is not sadness but a form of communication - probably not really linked much with an emotional state at all - then on into the school years crying is mostly out of physical pain (aside from my coercive 8 year old), then teenage years it's almost all emotional pain.
     So back to tough love, is it that we are being tough on our kids, or is what we have to do tough on our own emotional state.  It is most certainly not easy to listen to your child cry for hours on end as you are trying to teach him to sleep.  As with all things in my medical career I weight the risks and benefits of treating versus not treating.
    Not treating - benefits - child quickly falls to sleep with bottle, rocking etc.  Risks: child does not learn to self soothe, gets less quality sleep - if with bottle - may get dental caries - learns further manipulation of parents, parents get poor sleep and have less reserve to deal with now tired child.
    Treating: benefits, the opposite of the above, child learns parents mean it when they say it, learns to self soothe - quality sleep.  Risks: child cries for hours on end, parents are frustrated (although only for a short time). Parents feel they are forever scarring their child.

So Tough love I think means it is tough for parents to step back from their own needs and reactions to truly view the needs of their child not in a now sense but in the long run.  We don't want to see our children in pain, but by preventing pain early on we may ensue pain at a later date.