Colonization Of Colonial America

To show you just how strange it is that we have not met a civilization let me show you the math. Let's say that their typical colonies are ten light years apart, and now if we use the worst case scenario and say that their colony ships move at 0.02% of the speed of light, which is the fastest we humans have ever gone. Now, let’s say that it takes another thousand years to send out another colony ship, this means the the rate of colonization is moving at about .00019 light years per year, as the galaxy is roughly 100,000 light years long, this means that the entire galaxy should be colonized within 525 million year. And that is the most pessimistic estimate I have ever seen. If we increase the colony ship speed in the question to something highly more plausible considering future technology like to about 1/10 or one tenth of the speed of light, than that would mean we get the entire galaxy colonized in a mere 11

Which sounds like a lot but considering the age of the universe that is a blink of an eye. The galaxy should have been colonized many times over by now.

According to this line of thinking, the Earth should already have been visited by extraterrestrial aliens though Fermi saw no convincing evidence of this, nor any signs of alien intelligence anywhere in the observable universe, leading him to ask, "Where is everybody?". The galaxy should have already been colonized entirely millions of time over. Yet, no aliens are seen as of right now. There are many theories like that maybe it is the nature of intelligent civilizations to destroy themselves. Which means that once civilizations reach a certain point it is impossible for themselves to not be wiped out by themselves leaving the galaxy to others. Another popular theory is that It is the nature of intelligent civilizations to destroy others. This theory is not hard to understand, as examples of