With enough money and international coordination, we can push incoming asteroids out of Earth's path. We might even be able to bring back extinct animals in the lab. The problem really isn't scientific - it's cultural. We aren't yet able to coordinate ourselves as a global civilization to do something simple like bring food to a famine-stricken region. We can actually use current satellite technologies to predict where famine will strike next, but we can't get food there - usually for political reasons.