This suggests that a reaction from consumers who dislike Mr Musk’s antics are only one reason for falling sales. An updated Model Y, Tesla’s best-selling vehicle, has just gone on sale. In preparation Tesla ran down inventory of the old model, crimping supply. Customers doubtless held off purchases until the new car was available.

Trump told reporters he would write a check for the car, which retails for roughly $80,000, and leave it at the White House so his staff can drive it. The president also said he hopes his purchase will boost Tesla,