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Battleship Earth

Does the Pentagon have the right weapons to fight off an alien invasion?


As summer blockbuster season kicks into high gear, big-budget action movies like The Avengers, Battleship, and Prometheus remind us that there's one thing that unites Americans: Our shared fear of an alien attack. They also remind us that when the invading space fleet arrives, humanity is not going to surrender without a fight to our intergalactic invaders. Instead, we will band together to fight off their incredibly advanced weaponry with our ... well, with what, exactly? Are we really ready to battle our would-be alien overlords?

Luckily, the Pentagon's Defense Advanced Research Projects Agency, better known as DARPA, as well as some of the world's largest weapons manufacturers, are dreaming up the weapons of the future today. With the help of everything from lasers on jets to hypersonic planes to invisibility cloaks, we just might be able to make the battle for Earth a fair fight. You may think we're joking, but why else would NASA be uploading The Avengers to the International Space Station if not as a training manual? Here's a look at some of the most space-worthy inventions being cooked up now.


The official title sounds rather subdued, but don't be fooled -- this is an awesome laser beam. Currently in development at DARPA, these advanced lasers are being pursued because of their ability to "harness the speed and power of light to counter multiple threats." Weapons-grade lasers are actually a reality now, but are too big to be of use in an actual fight. DARPA, however, hopes to unveil a 150-kilowatt weapon that's light enough to attach to a fighter jet. Those will come in handy when the first sally of flying saucers emerges from the mothership.



Cara Parks is the deputy managing editor at Foreign Policy.  Joshua E. Keating is an associate editor at Foreign Policy.


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neilparry 5 pts

Dear Ms. Parks and Mr. Keating,

With all due respect, the members of the Galactic Federation of Light and numerous galactic federations and higher dimensional beings throughout this universe would like you to know that they are already here and have been here throughout many periods of earth human history, and that their overall mission here as Lightworkers  is service to planet Earth and her people.  Many of these civilizations are humanoid just like us.  However, there are some important differences for the newly awakened to understand:

Highly evolved beings do not resonate with lower emotions such as fear, anger, hatred, etc.  Love is their primary guiding force, service to others is how they manifest this love.  They wish us to know that we, too, can make quantum leaps in our evolution if we just embrace these simple truths. 

Not only are they more evolved spiritually as a collective, but they are also light years ahead of the earth human technology-wise.  They wish to share these technologies in order to free ourselves from the dependence of our current technologies which are wasteful and harmful to ourselves and all life including our living planet.  They wish to share truths about how the powers-that-be have purposely kept us in the dark about advanced technologies such as were garnered from the reverse-engineering of crashed space craft in Roswell, NM in 1947.  And, despite of the selfish gains made by our secretive government, and their desire to keep these technologies to themselves in the interests of "national security", the short answer to your question is a definitive, "No", the US or any other country still would not be technologically capable of fending off a negative alien invasion.  Right now, our biggest job is to fend off the constant fear-mongering in our media, which continues to portray almost all ET's in negative light to further benefit the war and 'defense' profiteering that is engaged in such an incestuous fashion between our governmental officials and the major defense contractors who are raking in billions and billions of our tax dollars, once again, in the name of 'national security'. 

Perhaps you might take a look at Dr. Steven Greer's website ( as a starting place to research some ideas about ET contact and about the ongoing efforts of many who wish to see an official acceptance of impending ET disclosure.  It is a difficult road we travel, as our politicians don't want to be seen with egg on their face when the truth is finally revealed, and the road is only made more difficult when we feed the flames of fear which are all but illusion. 


Many Blessings to All, as All are One

Rey_Carr 5 pts

The Pentagon is on the wrong track. Instead of investing in DARPA, they need to be developing methods to improve communication and understanding of aliens. Too bad they don't place the same amount of money in non-violent techniques of getting along with our visitors from space. Their continued focus on weapons shows they haven't learned anything from space travel efforts, science writers, and those of us who actually live amongst aliens. As almost any child can tell them, a species that's capable of travelling a gizillion miles through space to reach the earth is not going to be impacted by any weapons conjured up by the Pentagon, but they will be influenced by the universal principles of understanding and communication.

jac323 25 pts

We laugh and we should but there was a project called bluebeam or moonbeam or something like that where holographic images can be projected in the sky. Maybe we will see a hologram of a 100 foot Bozo the clown that we will have to worship and we will be all forced to wear big floppy shoes. Can we be anymore absurd?  An alien life form would look humans as we would look at ants. Why worry about something so remote and ridiculous?

Alexandros15 20 pts

In my opinion the only way to defend against such a threat is first of all being able to detect it, probably before it enters the solar system, then you must have the systems to fight this threat first in space so to be able to see how advanced it is, if they have the technology to come here and they are hostile, then the threat would be huge!

Welcome_to_Earf 5 pts

Hell yeah we can beat them! Just like a trebuchet can fight an F22 (500 years difference) or the Taliban can fight unmanned drones (50 years difference).

BeatThebot 5 pts

but.... what will happen if they are  pacific???????"Everyone knows that alien spaceships don't have to clumsily lumber down a runway before takeoff -- they lift off vertically with perfect balance" seriously????   hahahaha everyone knows this?????  alien   spaceships  does exists???  lolfunny post  ;)   a big joke from  media to the mass

EverybodyHatesChris 5 pts

Aliens that are pissed off at us would be attacking earth with a weapon called a Relativistic Kill Vehicle, an asteroid accelerated to a large fraction of the speed of light. There is no defence other than getting off the first shot.

bobfrommosinee 5 pts



Planet side is alway at the bottom of the gravity well, a losing proposition, But if they are here for resources and Lebensraum, dropping a rock big enough to destroy the indigenous life would also ruin any useful purpose for the aliens.

EverybodyHatesChris 5 pts

 bobfrommosinee  EverybodyHatesChris 


What if the aliens are attacking because they received out television transmissions and fear us? A relativistic bomb would do nicely.

MLite 5 pts

When are we going to get serious and just build a friggin DEATH STAR. I mean, that's no moon...

bobfrommosinee 5 pts

Later when their bodies were examined in the laboratories, it was found that they were killed by the putrefactive and disease bacteria against which their systems were unprepared. . . slain, after all man's defenses had failed, by the humblest thing that God in His wisdom put upon this earth. 

DeweyMai 6 pts

 bobfrommosinee Assuming they are CHON-based organic life with the same macromolecular schema. Granted though that if they want the Earth, organic is a distinct possibility. Great quote!

DeweyMai 6 pts

Let's fight interstellar alien invaders with terrestrial weapons. This article should have been published on April Fool's. What a joke.

dharkangell 7 pts

Sharks with freaking laser beams!

DanTanner 5 pts

How the hell would anyone know?

jhoughton1 5 pts

If aliens arrive, what we'll need to protect ourselves from is not their superior laser-rays but their cooties.

LuckyLuigi 5 pts

But will it defeat nazis from the moon ?

dharkangell 7 pts

 LuckyLuigi No, that's falls under anti-zombie defenses. Different department.

NeoracerXox 5 pts

This is a joke right? They would whoop our asses if they're only 500 years ahead, let alone 5,000. Another laughable display of human arrogance

SwiftrightRight 5 pts

 NeoracerXox Yes its a joke. Aliens with even a 100 year lead would just drop of few large rocks on our main population centers.

MikeLorrey 5 pts

dont forget the railguns

rus 10 pts

then what? China? Russia??? we go to the 3rd world war!!!! Wake up Americans!!

rus 10 pts

on the planet now the main threat comes from the American globalism (fascism!) and his financial group, killing people on the planet! Vietnam, Yugoslavia, Iraq, Somalia, Libya, Afghanistan, 'll Syria and then Iran the world! died in a 3rd world war, when free-thinking Americans do not change their government!

dharkangell 7 pts

 rus Yeah the main threat is the world's oldest functioning democracy a place where millions of people risk their very lives to get to every year. Clearly that is a much larger risk than a bunch of theocratic nuclear armed doomsday practitioners in the Middle East and Pakistan.


We're not perfect but a far cry from being the world's greatest threat.


One more point, the country closest to Fascism is China if you accept that the means of industrial production and capital, while being nominally in private hands, is fundamentally bent to the service of the state. But I'm guessing you and most other people do not really know what fascism is.

ObBop 5 pts

 dharkangell  rus   "There's class warfare, all right, Mr. (Warren) Buffett said, but it's my class, the rich class, that's making war, and we're winning"


"While the poor and middle class fight for us in Afghanistan, and while most Americans struggle to make ends meet, we mega-rich continue to get our extraordinary tax breaks," Buffett wrote in a Sunday New York Times Op-ed.


There has been class warfare going on," Buffett, 81, said in a Sept. 30 interview with Charlie Rose on PBS. It's just that my class is winning. And my class isn't just winning, I mean we're killing them."


"My friends and I have been coddled long enough by a billionaire-friendly Congress." - Billionaire Warren Buffett, in a New York Times op-ed on Aug. 15.

rus 10 pts

a simple capsule with a super-plague of our brothers in mind would solve all the problems as quickly as possible, effectively, qualitatively and without extra costs, but Hollywood, the Hollywood...(Americans zombie their Newspapers and TV!!!) zombie country manages zombie Americans

freetarotcardmeanings 5 pts

If there is no God, then there will be aliens. There will be an end and we have to be ready for any eventuality.

SIBelt 5 pts

I think we will need a lo of better fire power as such laser beam. For other species to invade earth only means that they have much more better technologies. Good luck <a href="">SI belt review</a> earth.

neax 18 pts

 the pentagon has failed to combat against aliens and the prove to the fact lives in the white house . soon to be corrected after november election .

EricInsalaco 8 pts

@neax Dumbass. Not relevant to the discussion. Do you have so much time on your hands and value it so little that you need to comment with hyper partisan (and inarguably hateful) political remarks on a lighthearted discussion of DARPA advanced projects in context of a hypothetical science fiction scenario like alien invasion? You are what makes browsing the internet and this site less enjoyable for everyone else than it should be.

kbc 11 pts

If there is God, there can be no aliens. Even god would hate to repeat his/her/it mistake. Moreover, most of religions tell us nothing about aliens. 


And if there is no God, then there will be aliens. There will be an end and we have to be ready for any eventuality. 

arvay 25 pts

Any life form that can solve the problem of interstellar travel would probably view us the same way we see ants. 

EricDavis 9 pts

 arvay The problem of interstellar travel is one of money more than technology. You could build an interstellar ship in 10 years. The problem is that it would cost several dozen trillion dollars. No one is going to spend that kind of money for a glorified science experiment.

SwiftrightRight 5 pts

 EricDavis  arvay Umm, your talking dollars, what you should be talking about is generations of total GDP of the entire world.

JoeCooper 12 pts

The gadgets are neat but really doesn't say a thing w/r/t aliens because we don't know enough.


One thing we do know about is relativistic rockets; basically if you accelerate a vehicle up to a notable fraction of light speed, the kinetic energy is like a hundred bajillion nukes or something.


The US Navy's Project Longshot and other similar research projects showed that this is possible with technology you could envision all the way back in the 80s. Longshot pitched a 400 ton upper stage using a somewhat conventional nuclear reactor to drive a fusion reactor to heat the exhaust mass. (Note that difficulties making a profitable fusion reactor are not a threat to this design; the power source is the fission reactor.)


The fun part is that these are practically impossible to defend against under the known laws of physics; we are at a technology level where we can, if we want, pick a planet and kill it.


Whether or not someone would bother is a whole other discussion, and one I think is more interesting. In movies they're always coming for our "resources" but that's  monumentally stupid.


Ongoing surveys are now suggesting there may be somewhere north of a hundred BILLION Earth-like planets in this galaxy.


Ours is unique because it has us on it chowing down on the oil, uranium, nat-gas, platinum group metals and other materials that nobody else in nature actually cares about.


In other words, our presence makes Earth a uniquely resource poor and (we'd like to believe) a uniquely difficult target.


I'll now present this script cut from Battle of Los Angelis.


Two aliens are in a room.

"I was thinking, man, we don't have enough water on our planet."

"Yeah, we should start desalinization."

"Yeah, that's cool, but I was thinking, why not get it from space?"

"Oh, like an asteroid? There's a million of those. Good idea!"

"No no no! We should go to another star system. Run a search for living planets."

"Okay... Hold on. Okay, I've got a list of four million we can afford to reach."

"Do any of them have military bases and thousands of nukes all over because they've been building up to a global war that didn't happen?"

"Uhh.... That one."

"Then that is where we shall find our water!!!"

"Aha! Wanting to test the new tevatron bomb, are we?"

"I was thinking more like running mindlessly into crowds with machine guns."

EricInsalaco 8 pts

@JoeCooper Ha! I like that hypothetical discussion, and I agree, I've always wondered what made Earth desirable apart from the many, many, many, many worlds that would ostensibly have the "aliens need that" material named in film. Water: comets, asteroids, frozen in sheets across liquid on entire moons; minerals and metals: ASTEROIDS; virtually any natural-state gas would be in solar winds or the clouds surrounding systems. Why would we be desirable? The only thing I can think of would be carbon fuels, I don't know with what abundance say petrol is found elsewhere, but if aliens still need petrol they have bigger problems than fighting us. That said, it's a fun little discussion to have.

Granten 22 pts

 EricInsalaco  JoeCooper Admittedly there is no guarantee that any extraterrestrial civilization would have the same mentality as humans, but assuming that they would act on the basis of similar desires* it would probably be to make sure that humans could not threaten them at some point in the future. From what we currently know is possible with technology the best way to stop an interstellar threat would be to preemptively remove it.


*A desire to acquire resources, end a threat, convert the ignorant to their divine etc.

MikeyClarke 10 pts

*sigh* Cue an army of commenters saying "The tech gap between us and any beings capable of interstellar travel is so gigantic that even if we fought them with a Tsar Bomb each, we might as well have stone clubs!!!!" Yeah, no shit. This article's just a bit of fun. Chill.

Granten 22 pts

 MikeyClarke I pointed out why I disliked this article. Unlike Drezner's, it isn't using a hypothetical to show how certain political theories work. It is effectively bragging about advanced technology that wouldn't be advanced in comparison. If they had simply done an article about advances in military technology I would have had no complaints about it.

MoonChild 5 pts

If only Iranians and Aliens were the same thing, wouldn't that be handy for testing these weapons?

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rwbwinski 8 pts

It just boggles the mind the amount of money we throw down a toilet pipe on new and better ways to kill folks...

bamaven 5 pts

Dream on ! If there are aliens out there and are capable of travelling great distance ( if they were close by, we would have known about it by now) to reach earth, I would  recommend that the earthlings meekly bend over and kiss their collective 'you know what' goodbye. The only lone hope is that the aliens with such light years ahead technologies also have a higher sense of what is universally right and wrong and decide not to have us with ketchup, lettuce, tomatoes between their ( or our)  hamburger buns!

Ghost Soldier 42 pts

Bath salts and lasers.  The future of America.  


No thanks. I'll take the ground soldier, the aviator/pilot, and the sailor.

Granten 22 pts

Frankly this is pointless. Any species capable of waging war over interstellar distances would be so technologically advanced that a war between them and Earth would be more akin to a war between Lichtenstein and N.A.T.O. The only hope humanity would have would be to wage a low intensity war and hope that the extraterrestrials don't consider razing the planet to be a tactic. Really this barely serves as a 'look how good our military tech' piece.

Ghost Soldier 42 pts

 Granten Relax, Francis.

Granten 22 pts

 Ghost Soldier Francis? And it's the truth. Realistically speaking, a species that can actually wage war on a planet that would be (at a minimum) dozens of light years away would be effectively unstoppable. I don't Drezner's articles on zombies because it's an effective way of explaining how different political theories handle international events. This just doesn't make sense and should have been rebranded as another article on advanced military technology.

StefanStackhouse 7 pts

This article is a couple of months late, it should have come out on April 1st.


Seriously, given that there is no place in space we have been that our robots haven't been already (and they are lengthening their lead), and given that robots are much better adapted to space exploration than we'll ever be, it seems logical to assume that if "they" are out there at all, if we ever make contact with "them" it will actually be with their robots. Rather than being hostile, they'll probably just be focused on taking pictures, gathering samples, etc. We might not even know they are here. Maybe they'll just be hanging quietly around on the opposite side of our solar orbit, out of view, until we've created hyper-intelligent robots that they can pal around with.


Any species truly intelligent enough to traverse the vastness of space would also be intelligent enough to realize that there are better things to do with their undoubtedly limited life span than to spend it hurtling through the void in a metal can; they'd leave that to their robots, and stay home enjoying lift. That is the answer to Fermi's Paradox ("If intelligent extraterrestrial life exists, why aren't they here yet?"), and the reason why we don't have to stay up at night worrying about an alien invasion - or spending money we don't have preparing defenses for it.

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