It is Christ-like to be an environmentalist.
Jesus said, speaking about how people treated others who were considered lesser than them, “Whatever you do to the least of these you do to me.” He meant that you should treat everybody like you would treat somebody important. Consider this – animals, plants are the “least” as well. Who says it just has to be for people?
If we are to “Love your neighbor”, then doesn’t that mean everybody and everything? God created everything. We show reverence to God by respecting God’s gifts.
Why find another planet? We will just have another to mess up. All that money on building a spaceship and terraforming another planet… Why not work on clean water and air here? Why colonize another planet? We need to learn how to get along and reduce our population here. We need to learn to live within our means, and be proper stewards of “our island home”, as Carl Sagan called Earth.
We don’t need laws for this. We need to change minds and attitudes.