US President Donald Trump rode a ceremonial lap in his armoured limousine and waved the green flag to start Sunday’s IndyCar race through the streets of Washington, capping celebrations of America’s 250th birthday. Trump, who created the Freedom 250 Grand Prix by executive order as part of the United States anniversary commemoration, had a prime view of the spectacle as open-wheel cars roared past iconic landmarks at speeds up to 298 km/h (185mph). “It has turned out to be bigger than we ever...