There are three scenarios on how we would react to the alien threat — and none very appealing. From Csaba Tóth, stand alone expert of science fiction universes.
Are we prepared for an alien invasion? This question usually inspires discussions about our level of technology, the quality and quantity of our weapons and our capacity to understand aliens. Rarely do we examine the political systems we have in place. This is a serious mistake as the biggest threat to our capacity to defeat unfriendly aliens results from the way we govern ourselves.
At the coming of aggressive aliens, the wisest choice from humanity’s perspective would be to form some sort of World Government: give all political and military power to an organisation representing all of humanity.
This is exactly what some science fiction writers imagine. In the Doctor Who universe, UNIT, a special organisation — endorsed and empowered by the leading world powers — dedicated to protecting Earth takes over whenever there is an alien threat to our civilization. In his bestseller science fiction trilogy, the Three-Body Problem, Liu Cixin describes how all major powers work together to direct their energies against an impending alien invasion. When faced with annihilation from aliens, it makes little sense to use national armies.
Unfortunately, humanity as such has no power over political and military matters — only states do. If aliens invaded today they would face not a united humanity but a collection of nations states all pursuing their separate interests; all trying to survive — or maybe even take advantage of the situation. Not because these states are inherently evil but because they care mostly about themselves: they want to survive.
No responsible political leader could blindly surrender his or her nation’s weapons to an organisation without receiving guarantees that their interests would be protected.
These guarantees are hard enough to negotiate in peacetime — in war, these negotiations would be impossible. Nations would remain as they are today and would find means of protection not requiring that they give up their sovereignty to a world organisation. There are three scenarios on how we would react to the alien threat — and none very appealing.
Scenario One: America First
There is only one way nations of Earth could unite: under American leadership. Given present US military doctrine and American military history, there is no way the United States would surrender control over its armed forces to anybody. Nor would the US give anyone a veto over what it does with its military. The Americans could be willing to take a leadership role against the alien threat and would probably accept the help of other nations — as long as they are in charge. This would be very unfair to everyone else as they would have to do something the Americans would not: give control to another nation.
However, given the fact that US alone accounts for half of the world military spending and probably the same amount of military muscle, accepting American leadership is simply an acknowledgment of existing facts. There might come a time when China or some other power rivals America and can make a credible case for leading the attack against aliens but in 2017, in military matters America truly comes first.
Scenario Two: Kill someone else!
Giving Americans power over the military forces of Earth would have been easier in the Obama or Clinton years — times when the majority of the world was more comfortable with the US president. For now, Donald Trump inspires little confidence outside America. If aliens invaded today, most nations would not wish to put their fate in his hands.
Thus, the fight against aliens would be a decentralised, chaotic affair in which most nations would hope that someone else takes the blunt of the alien attack. Most would try to preserve resources for after the war, undermining common efforts to fight.
Scenario Three: Alien allies
We tend to imagine our alien invaders as centralised, homogeneous groups who are united by one purpose only.
However, as humanity is divided, maybe so are aliens: groups and factions can have different goals.
Like in the new Star Trek series Discovery where was is the only goal that can unite competing Klingon tribes. Divide and conquer is an old human tactic and it is very likely that some nations would seek to ally with some or all the alien invaders.
While this would be termed ‘inhuman’ by some, political manoeuvring does not cease even in the face of imminent threat. The Catholic French once allied themselves with the heretic Turks against their fellow Christian Habsburgs; the Western democracies formed an alliance with the communist against the Nazis. Allying with forces once thought evil is a recurring theme in human history.
Humanity has so far been unable to unite to reach goals which would be technologically possible and which are in everyone’s interest: tackling climate change, eradicating poverty or stopping wars. There is no reason to believe It could unify against an external threat. We should hope aliens take their time and arrive only when — or if — Earth is more unified prior to their invasion.
(On the cover: scene from Roland Emmerich's 1996 sci-fi blockbuster Independence Day)