It launched, yes.
The Talmud is made of two basic parts: The Mishna (220 CE) and the Gemara (c. 500 CE). The oldest part of the Talmud is the Mishna, while the Gemara is commentary on the Mishnah.
This portion of Talmud is part of a portion of Gemara commenting on a portion of Mishna which says “These are they who are put to death by stoning:…” a long list of sexual sins as mentioned including “He who has sexual relations with a male” (m.San. 7:4)
The Gemara to this passage opens a discussion which revolves around two Torah commands: One against Sodomites in general and another against a man lying with a man as he would with a woman. The Rabbis break this down into two basic kinds of Sodomy: active sodomy and passive sodomy. Active sodomy is to sodomize someone else, while passive sodomy is to subject oneself to being sodomized.
The argument goes into great detail to point out that while he who sodomizes a child below the age of nine is obviously guilty of active sodomy he cannot be guilty of passive sodomy because the child is not capable of actively sodomizing him. The Gemara concludes with:
Rab said: Pederasty with a child below nine years of age is not deemed as pederasty with a child above that. … Rab maintains that only he who is able to engage in sexual intercourse, may, as the passive subject of pederasty throw guilt [upon the active offender]; whilst he who is unable to engage in sexual intercourse cannot be a passive subject of pederasty [in that respect].
(b.San. 54b)
Notice this passage does NOT say “If one committed sodomy with a child of less than nine years, no guilt is incurred.” And it does NOT say “A Jew may have sex with a child as long as the child is less than nine years old.” (That is just old Nazi propaganda).
What it does say is that if an adult sodomizes a child, that the child does not incur guilt and is not stoned to death.
The passage simply means that the man who sodomizes a child under the age of nine is guilty of active sodomy but not guilty of passive sodomy (allowing the child to sodomize him) which is actually a no-brainer which we would all agree with. If the sodmite had committed the act with a consenting adult he would be guilty both of active sodomy in that he had sodomized another man and passive sodomy in allowing himself to be sodomized. If he were guilty of passive sodomy as well, then that would mean that the child was guilty of active sodomy, and thus the child would be executed by stoning along with the adult.