Abortion should be illegal because even if they aren't considered "living" they should still be treated as a human being. Steve Jobs pioneered touch-screen phones and practically changed how phones are today, yet he was put up for adoption because his parents didn't want him (example of how putting a child up for adoption is better than aborting them), just because the fetus is not capable of human thoughts, does not mean it is not living and that does not mean it won't do anything in this world. All humans are entitled to "life liberty and property/pursuit of happiness," babies are humans, too, so they should be treated accordingly.
By the way, comparing a tree to a baby is stupid, a tree does not have thoughts, they are here to make oxygen and grow, meanwhile humans are here to think, be creative, dream, and live, which most of us aren't doing, that's why we are debating over this topic and getting nothing done, instead we could be trying to change this in the real world, but I am pretty sure no one has enough balls to do so in this forum.