Thoughts for a Countdown; Article 3

The article "Thoughts for a Countdown" talks about how earth first came about and how it was a glorified celebration. I agree with the author with his assertion that we "fall to [our] knees and kiss the carrier deck". The thing that caught my attention was when the author brought in the subject of "a visitor from another planet, or another century". He satirically uses this example to show the insanity and lunatic behavior of our world. We being fearing life on other planets because we are so used to life on earth and no where else. If there is life on earth, why can't there be life on mars? There have been evidence and associations of living things, but we are so afraid of it. All the science shows that there could be life, that microbes are just waiting to live and grow and create life. Why don't we expand life to another planet? or another world?