At some point, U.S. shale basins could run out of oil (though other non-opec countries with shale resources could make up for that). Or alternative energy sources could eventually displace oil altogether.
That is why SecState Clinton was trotting around the world selling Halliburton tech to our allies. And why Exxon will be running SecState shortly. Interesting that there's no mention here of the huge part banks played in all this. Their uncharacteristic patience. One imagines conversations such as, "If you just take the long view, you'll make a KILLING in about five years ..."