Something like Wing Commander 3: Heart of the Tiger. Where depending on how you're doing mission to mission, you can be pushed all the way back to your "Main HQ" and lose the war.
The mission tree for WC3 looked like this.
Depending on the outcome of a mission it would change the outlook of the whole war and if you lost enough missions you would be pushed back all the way to Earth where you had to fight a 'no win scenario'. It was awesome, way ahead of its time.
As for Squadrons campaign, its really solid and a great spectacle, but once most people beat it, they probably wont play it again, other than trying to beat a specif mission on a harder difficulty. Would be better if you had to make choices per mission and wasn't a totally linear experience.