Presidential candidate Ben Carson has issued a dire warning that President Obamas cancellation of the Keystone Pipeline has left the United States with virtually no place to store grain. Without the massive pipeline, Carson told Fox News, the nations network of silos is woefully inadequate to store the bounty of grain that we soweth. Carson said that as President, he would seek additional places to store grain, such as the hollowed-out heads on Mt. Rushmore. A nations greatness is measured by its ability to store grain, he said. I will return America to its former greatness. 