To me the number one billion is a very small number especially if you compare to commonly tangible items like gallons of seawater on the Earth or grains of sand. Even one billion minutes is not very long if it is weighed against the entire life of the Earth; 21 centuries is nothing. Hell, Zuckerberg is about to go from having a net worth of ~$17B to ~$28B by himself. Just another perspective.
=Laserjock=
You are correct....but we've messed up our little window a lot 50 yrs......an very small sand grain amount, but hey its the USA!!??
Mike