The last president to die in office was John Kennedy, in 1963. He was also the last president to suffer assassination.
Squeaky Fromme, a follower of the notorious Charles Manson, pointed a gun at Gerald Ford, but it had no bullets in it. She earned a life sentence in prison, but has since won her release. John Hinckley, Jr., a suburban schlub, did shoot Ronald Reagan in 1981, but Reagan survived.
Nothing is impossible, but killing a sitting president is pretty close. No president has ridden in an open car since Kennedy. The people who work for the Secret Service are well trained professionals who take their responsibilities seriously.
They would never say so, but it is a pity that they now have to work for a lout who is devoid of those qualities and entirely fails to appreciate their hard work on his behalf.
When Barack Obama took office, he had an extended debate with the Secret Service over his desire to keep using his Blackberry cell phone. They finally modified it such that he could continue to use it. Near the end of his second term, he got a conventional phone, sort of. It lacked most of the features people expect a phone to have for security reasons.
President Trump insists on using an unsecured phone, leaving his conversations potentially exposed to listening by agents of foreign powers. He is stupid and lackadaisical about security as he is about everything.
So now we learn that, always petty, he made fun of the physical appearance of the director of the Secret Service, whom he just fired. Given Trump’s poor track record with appointees, since loyalty to Trump seems to be the only qualification he considers, it seems highly unlikely that the new person running the Secret Service will be as qualified as the outgoing person.
One does not want to wish death on anyone, but it would be entirely condign if Trump enabled his own assassination by installing an incompetent crony as director of the Secret Service.