Quote - mysterious high flying aircraft that leave a Con trail that looks like someone blew smoke rings (Some type of pulse or ram jet i guess).

That would be the Aurora. Satellite photos have shown those trails leaving the Nevada desert and going straight out the Atlantic. Years ago when this was first reported, there were other satellite photos showing the thing coming in from the Pacific right to Nevada and not coming out. Also, there exists photos of those trails by ppl on the ground. Also, those trails have been recorded in seismographs.

Thoughts of the Aurora's propulsion has been everything from a pulse or ram jet to something like small explosions, similar to the Orion space project. In that project, a spacecraft would have traveled about the solar system riding on a series of nuclear blasts. Some years ago on either History Channel or Discovery there was a documentary of the Orion project, interviewing some of the ppl involved. They showed films of the tests they did of a modeled Orion space craft riding up a series of explosions. The most recent talk about Aurora is maybe the propulsion is something based on that.  If so, it could also be unmanned.

Whatever it is, it's fast!

About the SR-71... it seems every few years it's "retired" but then something comes up and one hears later that the Blackbird was sent for reconnaissance. I thought it was retired, but it's still doing missions. So I think that saying it's retired is just disinformation.