I think our best bet is not to f up this planet that we have right here to where other planets are a necessary option. Maybe making the other planets nearly impossible to reach or live on was part of the design. Kinda like how two species can't create rabbit-lizards or dog-birds. Some thing need to be left the frack alone. The energy required for a mass colonization of an inhospitable planet would be a drain on our already depleting energy resources here. Living in a bubble on another inhospitable planet would be hell on the human psyche.

In my opinion, before we attempt to live on another planet, why don't we prove it can be done by colonizing the ocean floor? If we can successfully do that, live in that environment where humans are totally foreign and can't survive without failproof technology, THEN and only then, should we attempt to colonize another world where there would be no chance of rescue should a catastrophic equipment failure occur.

Because from what I have read, everything currently living on this planet is evolved based on the many unique aspects of this planet. From the elements in the air, to the temperature, gravity, tidal forces of the moon, layers of the atmosphere, and even the magnetic field all serve a purpose in protecting or nourishing us.

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