Considering the number of galaxies in the universe, and the number of stars in each of those galaxies, and the number of planets that are orbiting those stars, I think a person would have to be extremely naive to believe that WE are the only intelligent species in the entire universe. And to believe that we are the most advanced, technologically, would, in my opinion, be equally naive and foolish. There could be civilizations out there that are MILLIONS of years more advanced than ours. So much so that we could not even comprehend things that their children do during playtime. Look how far our technology has advanced in just 100 years. Where will WE be in a million years? If we don't kill ourselves off, of course.
And personally, I believe one major reason the governments of this planet would try hard to suppress any FACTS proving such a thing as the existence of advanced civilizations, is exactly because it would be a tremendous blow to the ego of humanity to learn that in some cases, we might be the equivalent of crude unwashed barbarians in the eyes of some of these more advanced races. Surprisingly, quite a number of people DO believe that WE are the epitome of creation in God's eye.