I haven't read the book in a few years. iirc the Baron left Paul and Jessica in the desert so he could truthfully say he hadn't killed them.

Obviously, the book would have ended a lot sooner if he'd found a workaround, like telling Raban how badly he wanted them dead.

Trump has lived this long because, up until now, there was no one with the money and determination to kill him. His security is before he was elected wasn't that professional; at least two of his wives slept with their security men.