Bravo sir. This is what I have been saying for awhile. The Zod attack on Metropolis, Bruce being there, witnessing it and having no way to stop it all, this brought him back to that moment when his parents died I think. It's possible it's written that Bruce is emotionally spotlighting Superman for things out of his control. I really doubt even once the dust settles and all the information comes to light clearing Superman, that Bruce takes a deep breath and let's that emotion, that moment go. This is likely not about logic, it's emotion. Add in a Bruce that has lost Robin (Dick?) and possibly Gordon (no proof yet but... You never know) and let the Manor go to ruin over it perhaps... Well he's a Batman with more turmoil under the surface than usual I suspect. This could make him an easy mark for Luthor to goad into a confrontation. If Lex can set something up where Bruce's emotions and his rationality are in agreement then I think you have a Batman that easily sees himself as the one person that can stop this alien God on Earth. Some incident where to the world it seems Superman has done something unredeemable and Bruce wouldn't take a lot of time to consider all the angles, he'd act to end such a monumental threat.
This reminds me of an interpretation that occurred to me of the possible desert dream sequence (and my guess is that it is a dream):
Batman suffered the trauma of having felt powerless to prevent his parents' death, for which he has compensated by becoming the Batman. As a crime-fighter Batman also apparently was unable to prevent the death of Jason Todd at the hands of the Joker, which surely haunts him. So Bruce's loss of his employees during Superman's battle with Zod must tweak that core vulnerability within him: his sense of both helplessness and rage about those losses.
I'm going to assume that Batman, the World's Greatest Detective, has some insight into the effects of the trauma of witnessing his parents' death and his rage at a feeling of helplessness that Alfred describes.
But the desert dream may reveal an aspect of Batman's helplessness/rage that he may be out of touch with. And that is how much the Superman he fears symbolizes the darker qualities within Batman himself that he is unable to accept.
This is a speculation based on a speculation, obviously... but I think it is significant that Batman snaps someone's neck in the dream. Because as we know, both Superman and Batman share the same moral code to at all costs try to avoid killing. It is at that point presumably well known by the world that Superman killed General Zod by breaking his neck.
Thus, in this dream Batman and Superman are merged together through both their no-kill rule and breaking that rule.
If all this is correct, the dream about Superman could be viewed as a dream about Batman himself. And in this sense it truly is a nightmare. Through the image of Superman in command of fascist soldiers, the dream seems to present a vision of what Batman fears Superman could become, i.e., a tyrant, an abuser of power. But is it possible that that is something that Batman has been denying about himself as a powerful vigilante, and the tremendous rage that drives him?
The issue of avoiding killing is central to both Batman's and Superman's characters. Superman has his own reasons for the no-kill rule that we will set to the side for now. But for Batman, the moral code to never, ever kill is arguably a reaction formation. Bruce's own parents were murdered as he looked helplessly on as a child. Apparently due to guilt from it being so helpless about it, he became a vigilante who avoids killing at all costs so that he will never become like his enemies. However, it does not take a great stretch of the imagination to suppose that Batman has been repressing his own urges to satisfy his vengeance by killing the wicked ever since his parents died.
In both the teaser and full length trailer we see a scene in which the Batplane fires upon human targets and apparently kills them. Could it be that this more world-weary and jaded Batman has..."relaxed"... the no-kill rule?
In fearing what Superman may become, Batman is wrestling with ambivalence about what he himself is really and truly all about. We can easily imagine that Bruce has at some level asked himself whether it is true that, as Clark Kent warns Perry White in the BvS trailer, "This 'Bat-vigilante''s like a one-man reign of terror"?
Bruce himself states to Alfred in commenting on the condition of Gotham, "How many good guys are left? How many stayed that way?" The comment may in part refer to Harvey Dent. But perhaps the statement also reflects doubts that have festered in Batman about himself as well.
I doubt that Batman has 'snapped' because of all this internal pressure. Nor that he is unstable. But if what I'm conjecturing here is correct, my guess is that he will be driven by it with an extraordinary and singular force.
And again, we don't know the extent of Luthor's involvement in manipulating all this, if in fact Lex is indeed somehow ultimately acting as a puppet-master for the conflict, pulling strings unseen. (At one point Lex apparently has Superman kneeling before him in submission and the control he exerts to make that happen is unknown.) Lex Luthor's role is a big wild card in the hypothesis here.
But in the course of the melee to knock Zod through a building may have been next to impossible to avoid.) And let's not forget that Superman is honored with a heroic statue at the monument. 
) Lex would use the duplicate to do the frame up. If Bruce were to see with his own eyes Superman murdering a sitting member of Congress on live TV that would be enough to make his decision. Now I don't know what it could be. This was why, before this last trailer, my money was on a Bizarro gloss of some kind, either duplicate made from the scout ship birthing chamber tech or even a revived Zod somehow made to look like Superman. It would either break down or through some action by the heroes become a Doomsday or look more in line with classic Bizarro.The duplicate solved a lot of issues as I speculated about the plot given what we saw before this last trailer. Now... I'm thinking the odds on a duplicate have severely dropped.
