Re: The Star Wars 7 Thread (SPOILERS. SERIOUSLY. ALL THE SPOILERS.)
The most important aspect of the political situation TFA fails to establish is that the Imperial Remnants/First Order and the (New) Republic have signed a treaty. That's all we really to know.
The other two elements, that the First Order is working to undermine that by building a superweapon and the Resistance exists to fight against those efforts, is revealed in the movie.
That's enough for TFA. The conflict between Leia and the rest of the Senate over the course of action to take with the First Order may sound interesting on paper, it's not interesting to see a bunch of politicians debating and deciding to not take action or to take an action we as the audience think is stupid (because that's what it is - I can't think of any movie where this has worked, from 300 to Pacific Rim).
There are more episodes coming out and I would be surprised if the fallout from the destruction of the Hosnian system was glossed over in Episode 8 (opening crawl or otherwise). TFA was fast paced and based in the immediate aftermath, but the state of the galaxy now will likely serve as a key aspect of the story moving forward.