Well, the classic book about the persecution of Esperanto is Ulrich Lin’s “La Danĝera Lingvo” (The Dangerous Language), but it is in Esperanto as the majority of people interested in the subject are Esperantists (there is a German translation by the author, a German himself). Basically, both Fascist and Communist regimes jailed and executed Esperantists, because the “one world” pacifist philosophy and establishing contacts with Esperantists from other countries as is common to the movement didn’t sit well with governments that promoted cultural or ethnic superiority over other lands.
As for Modern Hebrew being a conlang, it is certainly at least in part so – Eliezer Ben-Yehuda created much of its vocabulary (and even some of its grammar) directly. But natural and artificial languages are really more of a spectrum than a real dividing line. When people make “rules” for English like “you shouldn’t split infinitives” or “don’t end a sentence with a preposition”, they are really proposing a sort of conlang based on English, as people do both all the time in natural English.
