A SETI Blog Feature

It is July 2nd, and Earth is besieged by a fleet of massive flying saucers positioned over every major city around the globe. Hours later, in a coordinated attack, they fire high-powered energy weapons into the heart of every city, obliterating the vast majority of Earth’s population in one swift decisive blow.

The following day, the remnant of America’s shattered military forces launches a retaliatory strike against the alien fleet’s mothership, but their attack falters when their nuclear missiles explode harmlessly against the spaceship’s impenetrable force field.

Then, on July 4th, a daring raid using the alien spacecraft recovered from the 1947 Roswell crash, infiltrates the mothership and uploads a computer virus to the mothership’s systems. The virus instantly causes a cascading failure of the force fields of the entire alien fleet, leaving them open to a decisive counterattack by national air forces around the world, and the day is saved.

Of course, most of you will instantly recognize the plot of the wildly successful science fiction movie Independence Day which smashed box office records around the world back in 1996. The film draws on the long-established theme of existential alien threats which began with such scifi classics as The War of the Worlds and Invasion of the Body Snatchers, continuing with movies like The Thing, The Arrival, and Dark City (a personal favorite of mine) all the way to recent box-office hits like Pacific Rim and Edge of Tomorrow.

In most examples of alien invasion movies, the day is saved by a few plucky individuals who, through sheer grit and human ingenuity, find a way to defeat the invaders and save Earth from annihilation. But while such gung-ho fare makes for great box-office, is it realistic to expect that we would be able to resist the onslaught of an advanced alien task force entering orbit around Earth with malicious intent?

I think the answer is clear…

No, it’s not.

To start with, any civilization capable of sending a manned mission across interstellar space will be light-years ahead of where we are in terms of technology, resources, and organization. We are still hundreds of years away from launching our own manned interstellar missions, and likely hundreds more from building an entire fleet of ships capable of traveling between the stars. Even then, the odds of our first visitors being just a few centuries ahead of us technologically are very slim. We could easily be many thousands, if not millions of years behind.

Next, when it comes to battle tactics, space is the ultimate high ground. As the failed Strategic Defense Initiative (or “Star Wars”) proved back in the 1980s, even defending against missile assaults from other Earth-bound enemies is extremely difficult, so what chance would we have of defending ourselves against a concerted attack by an enemy whose position in orbit gives them access to any point on the planet’s surface within minutes?

It’s not as though the aliens would have to bring an arsenal of planet-killing weapons with them, either. There is plenty of potent ammunition floating around above our heads that can be applied to the task, i.e. those near-Earth asteroids we already fret over from time to time. Science fiction certainly hasn’t ignored the possibility of turning space rubble into a means of planetary annihilation. Episodes of Babylon 5 and Stargate SG-1 have explored the devastating and unstoppable power of dropping big chunks of rock onto planets.

Of course, a lot will depend upon why these implacably hostile aliens are here. If they are on a mission of genocidal religious zealotry, then resistance will, indeed, be futile. Our only hope will be to hide in as deep and dark a hole as possible until they go away. Likewise, if they are intent on making Earth their new home with no regard for the planet’s existing tenants, we will be facing impossible odds.

Even if they are just making a pit-stop to resupply their fleet from Earth’s resources en route to somewhere else, we will have no better option than to stand down and let them take what they want. Getting in their way is only asking to be slapped down, mercilessly.

If conquest is their goal, things might be a little more hopeful for the resistance, but not by much. It seems extremely unlikely that our alien conquerors would need all seven billion human beings as slaves, serfs, or food, so culling the troublemakers (in the billions, if necessary) wouldn’t be too onerous a task. And it’s very unlikely that Earth would be their first conquest, so they’ll be ready for any resistance or insurgency we can muster.

As for the existence of that one overlooked, fatal weakness that plagues the aliens of science fiction–don’t count on it. Even if one did exist, odds are we wouldn’t get near enough to spot it, let alone have the time to formulate a plan to exploit it.

In short, if an alien armada ever swoops into orbit intent on the subjugation or destruction of the human race, it’s extremely unlikely we could do anything to stop them.

Now, since we’re likely to have some warning of their arrival, there may be some merit in squirreling several groups of people away in secure locations around the world in the hope that some will survive to carry on if the aliens don’t hang around too long, but if the destruction is too great, even that would only delay the inevitable.

Pretty bleak, all told, and our only real hope is never to meet an alien race bent on our destruction. Fortunately, I believe that’s a pretty good bet, for the reasons I gave in part two of this series–i.e. that we will be far more interesting and useful to them as objects of study or trading partners than we are as slaves or food.

In other words, even if one day we detect an alien fleet heading our way, there’s almost certainly no need to panic. Indeed, there is no point in panicking since there is little we can do, no matter what their intentions are toward us.

But even a friendly visit may cause us serious problems, as we shall see in the final part of the series, Unavoidable Consequences.