While this might be true I've developed a healthy suspicion of "for the children" reasons.
I can see how this could blow up utterly in our (US citizen's) faces -- consider the legal ramifications of 'combining' the laws for "child pornography" [which is a felony to possess] with the legal standards for 'children' on insurance... combining these definitions, we would have a system where any 'naughty pictures' of anyone 26 and under would qualify as child porn... and it wouldn't matter if it was a newlywed couple trying to entice each other or something that is perfectly moral.
It is exactly such a situation that I think we are coming to: the government has so many laws that you are likely technically breaking them continually -- and if they can make those felonies, well then, they don't have to worry about you having the right to keep and bear arms -- which is, I believe, how they will implement a defacto gun-control: making whole groups of people felons. (Which the majority will say should be barred from weapons.)
Personally I like Japan; I studied Japanese in college (and sadly forgot most of what I knew), they have interesting culture, and I like [some] anime (some is top-notch sci-fi [Ghost in the Shell, Crest of the Stars & Tenchi spring instantly to mind]).
I think it should be 18 as adulthood, period. Pretty simple.
Domo for a voice of reason .