Aside from the questionable morality of wishing another human being dead (albeit one who poses a significant threat to democracy), Trump's assassination would instantaneously transform him into a martyr in the eyes of his followers and most likely foment widespread civil unrest with further loss of life. His acolytes would claim it as evidence of 'deep state' intervention to prevent what would otherwise have been an inevitable election victory and perhaps even propel an even more dangerous individual in the shape of Vance into the Whitehouse. A classic example of being careful what you wish for.