This is a bit like saying, "I'm going to start this article on David Bowie by assuming he was really an alien."

First, take a look at UFO sightings. One of the most common behaviors is massive acceleration and direction changes which would result in hundreds of gs of acceleration.

It isn't just that no organic structure could handle that - but no physical structure we know of could handle it either.

Second, consider for a second that we see these craft in the daytime because they are shiny and silver, and at night because they are brightly lit up.

But why? If UFOs didn't want to be seen, if they have this amazing technology, why wouldn't they simply turn off their lights and paint them gray? Or if they did want to be seen, why these generations of coy hide-and-seek games? (I have similar questions about God, come to think of it.)

And finally, why is the government so laid back about this? Given the massive level of paranoia that the military displays, if they had an evidence that a superior military technology existed, they'd be flipping out and moving society onto (more of) a war footing.

There's one simple explanation for all of these - UFOs are simply a projection device, invented by the US military.

If you experiment with a bright flashlight, you quickly find out that you can make the beam move as fast as you like, or flick it back and forth and demonstrate unbelievable "accelerations".

There have been numerous reports of radar "bogies" encountered by organizations like the Mexican and Iranian Air Forces - where they scramble jets and fly around a coherent radar point that can't be seen with the naked eye.

My guess is that this is just another projection phenomenon, this time for radar.

I hate my answer, because it's boring, but it also fits the facts and doesn't require a new physics or a new cosmology.