Orbital element data for most of them should already be in the public
domain. I don't know how complete the NORAD data is, but I would think
that omitting a satellite because it was secret would only make it stand
out to an adversary with the ability to locate and track satellites
independently (especially given that one reason to catalogue them is
to distinuguish them from incoming warheads++).
++ shades of another topic - no one shouts conspiracy because we don't
go on nuclear alert for every meteor burst in the atmosphere, so why
shout conspiracy because invalid contact data is filtered out early.