The expert, who specialises in the changing face of war, claimed that UFO’s would send probes to scope out Earth ahead of the theoretical attack.
Professor Paul Springer, from the US Air Command and Staff College in Alabama, made the wild claims during an interview with the Sun Online.
Prof. Springer has spoken out after the Pentagon published a report in June admitting for the first time confirming there is something in their skies the US cannot explain.
Following the account, Congress and Senate have voted on a plan for a new dedicated UFO office to probe the phenomena.
However, Prof. Springer believes should an invasion take place, it would be like how Europeans colonised the Americas 300 years ago – resources bled dry and indigenous people wiped out.
He added that the aliens may well be nomadic, seeking out planets with probes in a bid to secure something they want and Earth’s nuclear weapons would be eliminated with lasers or improvised weapons such as asteroids guided to targets.
Other weapons used, could be a tailor-made virus that just wipes out the human population – leaving Earth ready to be picked clean.
During the interview, he said: “It is also possible that those civilisations that are making contact with us are having to adapt ordinary tools to be weapons.
We’re testing a new site:
“They may have to adapt what they have with them.”
When it comes to defence, the professor says that the military will have two priorities – survival and then capture of the aliens and their technology.
It comes after reports that an asteroid the size of a skyscraper, approximately 340 feet wide is heading towards the Earth’s atmosphere.
The huge rock has been labelled as “a potentially hazardous object” by space experts from NASA as it’s going to pass within 4.6 million miles from Earth.
Conspiracy theorists also reported aliens could be living in a ‘secret base’ inside the Earth after a UFO was spotted entering a Mexican volcano.
And reports claimed that alien life ‘unlike anything we’ve seen’ might be hiding in the clouds of Venus.
The colourless gas could well be a by-product of a living organism — or alien life — existing on the planet, once believed to be completely inhospitable.
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