You all are blowing this way out of proportion. First of all, you have to understand that Britain and British society is not like the United States. First, it is far more urban, especially if you exclude the northern half of Scotland and currently this program only affects England - which is very urban. Second, the yob and chav culture in England produces a real problem with youth crime and youth gang related crime. The majority of people (Labour, Conservative, Liberal Democrat) tend to focus their blame upon the parents of those youth who allow them to roam the streets, drink, smoke, gamble, etc at a very young age.
Therefore, Blair has offered this plan which is mostly voluntary as a way for poor parents to gain access to expert help. Where it is not voluntary is where a child has committed offences. Anti-social behavior orders (ASBO) in Britain are activities set by local councils that include things like vandalism, theft, flyposting, bullying, harassment, etc. This is no different than cities who fine parents or bring criminal charges against them for their children missing too much school or being criminally negligent in some other way. In other words, we do it here as well. The difference is that Blair is offering what he terms a "carrot and stick" approach as opposed to a flat out criminalising approach.
The philosophy behind this is that no one is simply a good parent just on virtue of having conceived and birthed a child. While some parents have the virtue of falling back to their parents or guardians for advice or memories of how to handle being a parent or perhaps they can purchase books, meet church officials, hire nannies, etc - not everyone has that luxury. In that case the government should step in to at least provide the possibility that these parents and children will have an improved opportunity to succeed at life.
The other option is to offer no support and allow the continuance of the status quo. Clearly that is not what Tony Blair finds suitable. Also remember that the British do not tolerate the levels of crime that Americans do.
I really don't see this as a case of nasty infringement on civil liberties. It certainly does not merit a discussion on Nazism.