The balloon was by the efforts of some group or other of self-appointed activists of no great relevance to anyone. Most people probably just ignored Donald Trump's visit beyond noting it from the news and newspapers, especially if they dislike him. Until he became the US President he was merely a property speculator who built golf-courses in (to him) foreign countries, especially preferring to locate them on environmentally or scenically sensitive landscape areas.
Yes of course we still have Stonehenge - it's not for sale, not even to the USA, and no, Mr. Trump can't use it for a gadget-golf course!