Star Trek: Discovery Episode 3.7 Review: Ups And Downs From Unification III
5. SB-19 And The Vulcan Withdrawal From The Federation (UP)
Once Burnham and Tilly have identified SB-19 as having something to do with the Burn (supposedly), Burnham and Saru take this information to Admiral Vance. He reveals that SB-19 was a study conducted by Ni'Var, formerly Vulcan, and that they felt the SB-19 experiment was the cause of the Burn itself.
SB-19 was a project that, it is revealed, they flagged as potentially dangerous, but that the Federation ordered them to continue with anyway. Once the Burn occured, they felt that they were responsible, even if the Federation had forced their hand.
This speaks to a running thread in this series - what exactly is wrong with the Federation? We now know that three of the founding members - Earth, Andor and Vulcan - have all left. In Calypso, we learned of the V'drayash (mentioned again by Zareh in Far From Home), which has been confirmed by Michael Chabon to be the Federation.
Starfleet are hiding in plain sight, and have at least semi-diplomatic communication with the former members, which begs the question: what's going on? What's wrong? What have they sunk to for these founders to turn their backs on the organisation? And, is the current form of Starfleet really something that the Discovery wants to be a part of?