Even I, personally, would be very upset that the president of the United States was assassinated. But, that the particular president of the United States that was assassinated was Donald Trump, I would, personally, celebrate, probably, for several months.
My biggest objection would be that he’d become a martyr, and MAGA would gain adherents. I’d much rather he have a very public massive coronary, preferably as soon as possible. That, I would celebrate with no guilt whatsoever.