Paedophilia is unfortunately just like many other "problems" that are inherent in human society. If the problem is big enough and difficult enough then "authority" is always reluctant/slow/incompetent at dealing with it – and that's just another facet of human nature where we all like to deal with the easy problems and leave the difficult ones on one side. Isn't that why we find it difficult to get rid of a failed trade, spend a lot of our energy on the entry – which is "fun" and the reckoning doesn't come until later (just like using your credit card?).
Isn't that why great politicians are as rare as great people: they are the ones that see what needs to be done and make it their business to do it. In the current context I see Prime Minister May as someone who likes being PM but doesn't have much clue as to what needs doing and even less as to how to do it. Contrast this with Thatcher: whether or not you agree her politics, she at least knew what she wanted to do and how to go about it and I suspect her motivation in being PM was not the glories of office but the attraction of a post where she could achieve objectives.
But going back to paedophilia – as in most things, what gets reported and what we get to know about is usually only the tip of the iceberg and there are countless vested interests in having it stay that way. That may sound a bit like conspiracy theory but it's only when these things get exposed you realise how awful it is – just look at the nonsense that was going on in Rotherham and is probably going on elsewhere. Do remember that the frontline of enforcing the law is with the police force who today, just like Lestrade in Sherlock's time are not always the brightest of the bright and they themselves cling on in opposition to having a proper "officer class" like they do in the Armed Forces, which is one of the few places where I have seen efficient management backed up by expertise.
Too often, the enforcement authorities are leaned on by those in political control – but hey that's been going on for centuries hasn't it?