"Lord Vain" wrote
.... but the DOD also wants to use it (may even be funding a large part of
it)
for their hunter-killer satellites but they insist on secrecy. ...

This is indeed the 'conventional wisdom' but my own investigations
have persuaded me it is a 'bad guess'. The DoD seems to want the capability
to inspect unusual and suspicious 'other' space objects, but even more, it
wants to ability to inspect its OWN space objects for unexpected failure
modes or deliberate interference. An auto-rendezvous inspector could be
stationed at a refuelling/recharging bay aboard a valuable US space asset
and act as a defending capability.

Also, for actions against 'other' space objects, autonomy and on-site visual
inspection
(and nearby loitering to intercept narrow-beamed comm links) is much more
important at larger distances from Earth, such as the GEO arc.