As catnip for a high-end mendicant like Donald Trump, the Boeing 747-8 is unbeatable. It’s an exquisite machine, a perfect consummation of form and function and last in a line of one of the greatest airplanes ever built. It’s also a haunting specter for Boeing of a supremacy it achieved and then lost.

Donald Trump wants to accept a Qatari jet to replace ageing Air Force One planes, but the constitutionality of it is disputed. Here are the facts.