Is Human Survival Important?

Why do we care about human survival? I'm not referring to the fact that we want ourselves and others to stay alive and be well, but the idea that the human race needs to go on forever. I was watching a program put together with the help of Steven Hawking, and he brought up the fact that our planet is likely to be damaged beyond repair at some point, whether by ourselves or outside factors. He suggested that this made it important for us to move into space.

This feeling that it "we" need to continue on is a common sentiment. I stopped and thought about it, though, and I can't really think of a good reason why this is an important goal. Perhaps I just don't feel the same way, and this may be indicated in my unwillingness to - and lack of desire to - have children. I don't want immortality through my kids, nor through future humans - I want it through not dying!

It isn't that I don't care about people. Quite the opposite. I want to see everyone happy and well-fed. I am personally against almost all wars that have happened or will happen (I think there are more options than we realize). I try to help others when I can, and not out of religious duty, but because I easily empathize with their suffering. But these are people who are here now!

Can it really be that important that those who are not here yet all get born? Why? If we all stopped having children, and we just enjoyed the time we had left on Earth, humans would likely be gone in about a hundred years, but so what? Is this a tragedy? We almost all could have more children and choose not to bring these potential lives into existence, so why does it matter if we bring any into the world?

I'm not suggesting any answers here, and I realize that the "human race" means a lot to some people, even though they may not care much for many actual humans. I just don't see how it can be meaningful if we are someday gone, since meaning is a human invention (at least our particular form of it is) and it would be gone with us. Human survival? Let's aim for keeping the ones that are here alive and housed and forget about the future of the human race in space.