some of which will hit earth

Hopefully in one particular spot.

Joking aside, if there is going to be a lots of debris hitting us, I wonder how much warning we'll get.

Also if it does hit the moon, what are the chances of mankind realising once and for all that we are on a small fragile rock zipping through space and we'd be better off taking care of it instead of petty bickering about what toilets people are using?

I won't hold my breath.