Here it is what Leviathan has been doing since 1930: grow, grow, grow.
It seems spending during the WWII was quite small compared to what happened next.
It also seems Nixon did the best he could have done to the benefit of government growth by breaking down the Bretton Woods system and making the US dollar an irredeemable paper currency.
"Every irredeemable paper currency in history has failed. Yet, the experiment of the US dollar and the rest of the fiat paper world continues."
http://mises.org/story/3281