"Man, I hadn't even thought about what happens when we go back."

And Luke's going to continue not thinking about it until such a time as he can't ignore it.

"For now all we can do is whatever we can with what's right in front of us." Trying to worry about what's going on back home isn't going to help. Not long term. They can't do anything about it. But they can do stuff about the situation they're in at least.