Idea I was working with is that even in the current situation there is going to be serious resentment on Minbar as most people won't know how precarious their position was. Branmer's overall strategy wasn't a bad one given the circumstances against him but he really needed to end on a win.
He wanted that raid on Earth to work, to knock out some of the EA's infrastructure and show they were still vulnerable to the Minbari. THat should have been enough to force a peace leaving Minbari honour more or less intact. In some of the background stuff it talks about how his clan were originally cavalry based warriors who were experts at raiding behind enemy lines and striking critical targets. He would have presented the hit on Earth as the modern version of this and a good place to tie things up.
Except of course he lost and then had to endure the exact same thing as the allies raided Minbar demonstrating they were vulnerable. While he prevented catastrophe he still lost the jewel of the Minbari orbital grid and the Grey Council. THe morale damage would have been near total and while it did at least let him end the war it ended on a defeat. That isn't going to be popular.
Branmer remains in command but he is not in a strong position. He is a traditionalist and expects simple obedience but he hasn't quite grasped how much Minbari society has changed. He can't count on universal support because of his rank, those under him are questioning his decisions some of them in public. There is a more radical group led by some in the council that rejects Valens ways and seeks to go further back. THis is a little like Shakiri in the civil war but much more pronounced, fierce and with wider support.
While Branmer is focused on the Shadows he hasn't noticed the divisions or the growing calls to fix the disgrace of the war by putting Earth back in its place.
Now on the other hand Earth is doing better than canon. Because they ended on a win and because a lot of the League actually did help there is less bitterness. This reduces the acking Clark has but doesn't eliminate it, Earth still took heavy losses in what is seen as an unjustified war so there is still plenty of anger and hate for the Minbari.
There's also plenty who wanted to see the war go on until there was a clear victory and didn't agree with a negotiated peace, they wanted a full surrender which would of course require glassing most of Minbari space. The President wasn't ready to go that far, but plenty of others would.
Earth was strong but couldn't have taken Minbari space alone, it would have needed the Centauri for sheer numbers. The Narn and League wouldn't have been enough and the EA wasn't ready to see the Centauri gain that level of extra strength. EA didn't have the numbers after initial defeats or the necessary modern ships, they were still short ranged fuel hungry zero g ships mainly.
But by the series Omega class ships are the backbone with dozens of shiny new Warlocks at the sharp end, both designs able to range freely across Minbari territory. Not to mention of course Shadow tech under experiment. THis would give Earth the power to win a solo war without outside help, which suits Clark and the EF hardliners.
THat would be the political situation, Minbar is increasingly divided and turning away from their Valen principles while also mass producing top of the line warships. THis is for the Shadows but no one believes that and most see it as rearming for revenge. Meanwhile Earth is also churning out high end ships and mobilising because it thinks round two is inevitable.
The Narn are bouyed by their win and are adapting stolen Minbari tech making them more dangerous, and in response to both them and Earth the Centauri are also tooling up their battle fleets. In turn so is the League though less efficiently and in this scenario the Dilgar are aligning with Earth and Narn.
Tensions are high, things are getting unstable, and everyone is much better armed and ready to fight than canon. Such is the set up for the follow on.