Ultimately what happens or doesn't happen here that involves government is determined by the voters. Who gets elected on whatever platform is the choice of the people by voting or by being silent ("silence is assent", remember), as was set up by the "founding fathers" that authored our Constitution.
If the majority of the voters aren't informed, or aren't objective about who they vote for, or don't pay attention enough to learn all that's to be known about the candidates, or don't question the ravings and rantings of propagandists and instead take them for truths in an abdication of their duties to learn and think for themselves, or have forgotten the whole compass of what the US is supposed to stand for, and a host of other irresponsible actions (or inactions) as citizens, then we get a bimodal Congress populated and directed by mediocre intellects with hidden but knowable agendas that won't govern, won't see to the general welfare of the people and a healthy direction for this country.
In short, if the government is incompetent, agenda driven and unable to negotiate and compromise within to get things done, ultimately it's the fault of the voters who elected it. It would take 2 election cycles to fix if the majority of voters would smarten up and demand objective, intelligent governance by electing intelligent, objective representatives.