^ Isn't it about people feeling attraction towards prepubescent children? That's the crux of the matter, they like children, not teenage girls/boys who have already developed a much more mature female/male outer appearance.
The other thing you mentioned is about defending the younger one's rights and vulnerability. I stated somewhere before - in almost all cases, the older one can take control and manipulate the younger person affected because they have more power (physical and/or financial, social etc.).
You last example is about the age of consent and is different in every country. The major reason for this is to protect minors from being abused. You might argue that a sixteen-year old knows what he or she is doing, but this is doubtful. We're talking about an age where most young people are trying to find their own identity and place in the world. Insecure, sometimes unpredictable, their behaviour and decisions can't be compared to a thirty-year old's.
Paedophilia is when this attraction toward younger people is taken to its extreme. If a 30 year old person, male or female alike, wants to pursue sexual relations with, say, a 7-year old child, that is just wrong. The seven-year old wouldn't be able to do anything to prevent it from happening, neither in terms of physical force nor psychologically. Isn't it the case that victims of sexual abuse are blackmailed into keeping the whole matter quiet? Imagine what it is like for a child if it is told that it's a very very bad person if it tells uncle Jim's/aunt Jenny's little secret? Exactly.
Sexual abuse scars people for life. That is to be prevented, and therefore, certain laws have been made. One can argue where to draw the line, but some things, in my opinion, aren't up for debate.
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@Casey: Have you tried behavioural therapy? I mean something where you would be confronted with your phobia and slowly re-train your bain to 'accept' spiders without a too extreme reaction. I heard it helps.
"All scientific advancement due to intellegence overcoming, compensating, for limitations. Can't carry a load, so invent wheel. Can't catch food, so invent spear. Limitations. No limitations, no advancement. No advancement, culture stagnates. Works other way too. Advancement before culture is ready. Disastrous."
There's definitely truth in that...