I don't think european, japanese, or even other US IXP's require NSF's
"stamp of approval." I was pointing out there are a number of IXP which
were not created by NSF's process. But some folks think "NAP" refers
only to the NSF identified exchange points, and unless the government
approves your NAP, there is some type of anti-trust issue with ISPs
deciding to exchange traffic at a non-NSF NAP. I don't think that is
true.
The NSF stopped funding all the NAPs several years ago. Other than a
historical oddity, there is nothing different about the NSF NAP and
non-NSF exchange points.