Star Trek: Picard is presenting audiences with a decidedly different version of the iconic captain - one who is no longer a member of Starfleet. In the trailer for the much anticipated CBS All Access series, it's revealed that Picard is retired from the organization and spends his time tending to his family vineyards in France, echoing the possible future he glimpsed in the Star Trek: The Next Generation series finale "All Good Things."
The Star Trek: Picard trailer's narrator seems to be a Starfleet officer commending Picard for his achievements and some sort of personal sacrifice he made 15 years earlier, while questioning why he left Starfleet in the first place. That question is pointedly left unanswered in the trailer, and figures to be a primary driver of Picard's story. We may not know the exact reason Picard left Starfleet behind, but there are some clues.
For one thing, we know the dissolution of the Romulan Empire has had a profound effect on Picard. At first glance, this is a somewhat curious development; Picard never had much of a relationship with the Romulans, who were one of TNG's lesser villain species. The one major exception is "Unification," the classic TNG two-parter that saw the meeting of Picard and Spock. In that episode, Spock - the Federation's ambassador to Romulus - goes underground as part of a movement to reunite the cousin races of the Romulans and Vulcans. Picard had a pre-existing relationship with Spock's father, Sarek, who had recently died without making peace with his son. Picard and Sarek once shared an intense mind meld, and Picard allowed Spock to mind meld with him so that he could understand how much he meant to Sarek.
Per the events of J.J. Abrams' 2009 Star Trek film, we know Spock remained ambassador to Romulus several years after that, and attempted to save the planet from a runaway supernova, but was unsuccessful. It's easy to imagine Picard attempting to help Spock in his diplomatic efforts over the years, and the loss of both Romulus and Spock - though we know Spock survived and simply ended up in the Kelvin Timeline - may have been enough to break Picard's spirit.
There's also the possibility that Picard lost something much more important to him - the Enterprise. The trailer narrator suggests there was a great calamity 15 years prior, presumably the destruction of Romulus, and that Picard took part in a valiant rescue effort. If the Enterprise and its crew was somehow lost during that mission, it would explain a great deal about why Picard has seemingly withdrawn from the organization that so defined him.
We don't know the answers yet, but if nothing else, Star Trek: Picard promises to be unlike any other show in the franchise's history; it shows us what happens when our idealistic future heroes don't get the happy ending they might deserve.