Do you believe that there is any danger in a government deciding to target criminals who they think might likely commit a crime in the future (but haven't yet)?

Yes because there are so many factors that can change before that time comes. plus every person by law is innocent until proven guilty in a court of law. And for that to happen they would need hard evidence to prove or convict that they were going to do it.

a fable" i don’t have much to go on

i think that the answer is substandard.