I believe in the last two (far away galaxies and other wavelengths)

 

I think it's likely that all of these things play a role to one degree or another. I would be shocked if there isn't other intelligent life in the universe, but it may not be close and we are early enough in the life of the universe still that even an advanced civilization would have difficulty colonizing entire galaxies, for example. They also may not want to, they may have other priorities.

 

My beliefs are based around empirical evidence. I don't believe there is or isn't like out there, just as I don't believe there is or isn't a God. If there is life, they're probably smart enough to know we are the universe's HIV. If they contact us, we will infect them.

 

Or then again, maybe intelligent life HAS been to Earth, the government knows about it, it's hiding the fact, there's a frozen alien in a military basement and the secrets are locked away in a filing cabinet deep underground somewhere....

 

^^^ Nope. If that was true, Trump would've Tweeted about it by now.

 

He may be the President, but that doesn't mean they've let him in on all the country's secrets, alien or otherwise.