Extracted from “Where are They?” copyright Arthur C. Clarke (1986):
UFO skeptic Arthur C. Clarke (1917-2009), credit: Wikipedia
“Nowadays, anyone who considers that alien supercivilisations may exist has to contend not with skepticism but with something much worse – credulity. Although the subject now effects me with uncontrollable fits of yawning, I would be failing in my duty if I did not say something on UFOs.
“So here, as briefly as possible, are the conclusions I’ve come to after more than fifty years of study:
“1. There may be strange and surprising meteorological, electrical, or astronomical phenomena still unknown to science, which may account for the very few UFOs that are both genuine and unexplained.
“2. There is no hard evidence that Earth has ever been visited from space.
“3. If that does happen, there are at least three independent global radar networks that will know within a matter of minutes. And in the unlikely event that the US, [Russian] and Chinese authorities instantly cooperate to suppress the news, they’ll succeed for a maximum of forty-eight hours. How long do you imagine such a secret could be kept? Remember how quickly Watergate unravelled.
“Having written thousands of words on the subject (and read millions) I refuse to go into further details. If anyone wants to argue, I’ll merely quote one of my favourite book titles: ‘Shut up, he explained.'”
David Clarke is Associate Professor in the Department of Media Arts and Communication at Sheffield Hallam University, UK. He teaches media law and his research specialism is contemporary legend. Previously he worked as a journalist for The Sheffield Star and Yorkshire Post and spent four years working as a Press Officer in local government. His PhD in Folklore and was completed at the National Centre for English Cultural Tradition, University of Sheffield, in 1999. From 2008-13 he acted as consultant and curator of the MoD UFO files project with The National Archives. His books include The Angel of Mons (2004) and How UFOs Conquered the World: the history of a modern myth (2015). In 2018 he co-founded the Centre for Contemporary Legend at Sheffield Hallam University. This blog covers his twin research interests in journalism and folklore. The views expressed in the contents are entirely his own.
drdavidclarke.co.uk 
Radar networks dont usually give worldwide alerts for UFOs when they receive unidentified radar echoes. Imagine if they would.
Also, if we for a split second assume even the tiniest fraction of UFOs – perhaps a fraction of only the ones observed by trained military observers and aerospace engineers – to be genuine, it is hard to believe any nation, let alone a superpower or three, to admit that there is something in the air they cant explain or shoot down.
The Military Mind isnt well known for publicizing its shortcomings and strategic weaknesses. It is, however, pretty good at keeping secrets in its chain of command. Sure, Watergate blew over quite fast. We still have no idea what black project B-2 successor prototypes DARPA is currently working on, and yet, few people would deny that they probably are working on top-secret plane somewhere hidden. So there are secrets that manage to stay hidden for a long time despite being known to a lot of people.
Just saying. Even if 60% of sightings have a perfectly profane explanation, and close to 40% are high-tech prototypes (also profane i suppose), call me a crackpot, but I’m keeping an open mind.
You make some good points here Alex. Seems to me keeping an open mind is the only sensible thing to do.
These statements from Clarke can, probably, be countered by his own three Clarke Laws!!
http://en.wikipedia.org/wiki/Clarke's_three_laws
Even if we ignore all the unknown lights in the night sky what remains are tens of thousands of daytime sightings of flying discs.. IF we ignore all those sightings we have tens of thousands of people who claim to have been abducted by aliens.. IF we ignore those who claimed to have been abducted at night because we want to blame it on sleep paralysis we are still left with several thousand people who claim to have been abducted by aliens while driving or otherwise completely awake and alert.
I do not know what the explanation is but i do know that the explanations that skeptics offer are often more ludicrous and ridiculous than an extra-terrestrial hypothesis.
And by the way, we have stealth aircraft that are invisible to radar, why is it assumed that e.t.’s spaceships do not have a similar design? Are they not as intelligent as we are?? Human arrogance infuriates me.
Can you give an example of a sceptical explanation which you find harder to believe than an ET explanation? Thanks.
Yes, that all UFO stories can be explained. Quite clearly some can’t.