Perhaps this is just a huge case of "duh, that's obvious." Perhaps we choose to just ignore this. Perhaps everyone really knows what's going on and we just choose to to be apathetic. Was it meant to be this way? Are we being callous in badmouthing the democracy we live under by saying "um, hey... progressive taxes are nothing more than a way for the political elite to get and stay elected?" This isn't a revenue versus spending problem. It's an ethical problem. It's a perversion of representative democracy problem.
Scottish lawyer Alexander Tytler is credited with saying (yes, this has circled the internet many times), "a democracy cannot exist as a permanent form of government. It can only exist until the majority discovers it can vote itself largess out of the public treasury." In short translation: our elected representatives do not directly give the electorate money, but, but promising to take less from them, they will win favor from that electorate and continue to get elected to that position. Tytler went on to say, "after that, the majority always votes for the candidate promising the most benefits with the result the democracy collapses because of the loose fiscal policy ensuing, always to be followed by a dictatorship, then by a monarchy." This goes back to the "duh, that's obvious" quote. We might not be headed for a dictatorship per se, but democracy as it seemed to be intended, under a progressive tax rate system, does not truly exist.
Economics tells us to look at things in models of the simplest form. Here is an example of that (you might notice a little bit of facetiousness in this example, you might not). For this illustration, we quickly look at a model voting area (it could be a country, county, state, etc.). The only things we know about these data are the relative incomes of the voters and the positions of the two candidates campaigning to be this area's representative.