To each according to their needs, determined by the State

Playwright David Mamet has a long piece about gun rights in Newsweek, but this part stuck out for me:

President Obama, in his reelection campaign, referred frequently to the “needs” of himself and his opponent, alleging that each has more money than he “needs.”
But where in the Constitution is it written that the Government is in charge of determining “needs”? And note that the president did not say “I have more money than I need,” but “You and I have more than we need.” Who elected him to speak for another citizen?
It is not the constitutional prerogative of the Government to determine needs. 

And yet there was the President, only a couple years ago, declaring that "at a certain point, you've made enough money."  This is all part-and-parcel of his populist war for "fairness" where - gosh darn it - those rich jerks are eating all the pizza and we have to eat the box.