The United States bought Alaska for peanuts in 1867 — about $125 million in today's money. Greenland would be much more expensive to buy at a time of many other demands on the public purse. It's not like buying a golf course where you go to an attorney and say 'Can you sanction this?' Even if you got an agreement in principal, the price would be extremely high. If this were to go ahead, it's going to be in the billions, possibly even trillions." - Professor Iwan Morgan