Sorry, why is it an impossibility for people in power to die?

I'm not advocating for violence, to be clear, and in the novel KSM seems to take the stance that at some point violence is really counter-productive. But certainly there have been places and periods in which e.g. targeted kidnappings of rich people, assassination attempts on politicians, and terrorist attacks against high-profile targets have all been around -- why do you think is it impossible for those to be directed at people in power in the future? Especially if there are progressively more climate victims, it seems like we're setting the stage for a generation of people to be ripe for radicalization.

TMftF heavily hints and at times outright describes the existence of secretly funded UN blackops missions that target and assassinate people in power with strategic importance. It's been a few months since I read it, but if I can recall, it also described it's connection with ostensibly grassroots eco-activist/terrorists.

Submarine accidents not withstanding, I'm not convinced the UN in our current timeline could be transformed into one that engages in this behavior.