Imagine you are God and you decide to create a universe. When you create this universe you set it up as a game with three broad conditions. To “Win” the game two intelligent species have to meet each other and communicate.
Broad Condition number 1: Entropy
The Universe begins with a huge injection of energy. You have this big bang which creates all these galaxies, stars, planets and moons. From the point of origin they will all drift outwards. As they drift outwards the energy of the creation will eventually dissipate. The end state for this creation is death. Cold dead pieces of rock drifting ever outwards away from each other.
Broad Condition number 2: Evolutionary time
In order for these intelligent species to meet each other the species must firstly evolve. You cannot put icing on a hot cake straight out of the oven. It has to cool down. The steam has to evaporate. The conditions need to be right. So in this universe it takes time for life to develop from primordial chemical soup.
A couple of billion years for development of photosynthesis so that oxygen can be produced.
A billion years to the development of Eukaryotes and another billion to develop into multi-cellular organisms. And all this time those galaxies are drifting apart, drifting apart.
Then things can speed up. From the first multi-cellular organisms it only took another billion years to see the arrival of hominids. From the arrival of early hominids it only took a million years to the arrival of civilization. Then it only took 7,000 years for us to leave our planet and reach the moon.
We reached the moon in 1969. With a bit of luck it may take only 100 years from there to put a man on Mars. But even then we will not have reached Level 1 on the Kardashev scale and if we are to “Win” the game we will need to become a Level 3 Kardashev civilization. We need to become a Galactic civilization.
Broad Condition Number 3: Resource Constraints
Here is a sting in the tail. Each origin planet for a species is given a delicately balanced resource package. If those resources are not managed sensibly there is a strong possibility that a developing civilization will implode before they make the great leap into space. Civilizations rise and fall, rise and fall over time. But few of them have ever tested planetary resources in any meaningful way, except ours.
At the rate mankind is destroying this planet we will have poisoned our environment long before we reach Kardashev level 1.
That Fateful Meeting
And let us pretend we somehow achieved that meeting with another civilization in space. How many humans would suggest a shoot first approach to communication? We have a poor record of engagement with newly discovered tribes and peoples of men. How would we fare with an alien species?