"They may only be fighting us because we have the means to fight back" is a stupid reason to go around undefended. Not only is it nothing but a theory, but it leaves no contingency plan in the event that your theorycrafting went horribly wrong. It's not really that tragic - people aren't omniscient and survival is about making the best choice based on the limited information you know.
You could always look back and say "if we this then, none of this would have happened", but that's unrealistic.
If it is necessary and logical choice of action, then I cannot condemn them for taking it. While it initially felt wrong after witnessing the events AoA and not knowing the reasoning behind it, the GTVA feels as reasonable as the UEF. Neither side on a whole is considering the reasons for why the other side is fighting, really, though the individual soldiers on the battlefield do. This makes it more interesting.