admit it has exotic surveillance platforms that American citizens commonly mistake as being "UFO's".

The reason so many Americans create petitions for government disclosure on aliens is because of the sheer volume of classified platforms that litter our skies. These advanced platforms have exotic shapes and materials that reduce their RCS/visible/thermal signatures.
They look so exotic that people cant help but assume they must be from outer space.
In fact NRO historian Gerald K. Haines writes that half of all the UFO sightings in the 50's, 60's, and 70's were CIA reconnaissance craft. (from the CIA's web site)
But the wall of secrecy continues. Now the Department of defense is even classifying helicopters like the one used in the Bin Laden raid. If the White House wants to foster trust with America it needs to start disclosing these platforms now before one shows up on 60 minutes.