America has a republic, not a democracy. By design. A democracy lets the people rule directly. In a republic there are intermediate officials who in fact mediate among the contending factions. For much of U.S. history, that mediation was done by the major political parties. In a provocative article in The Atlantic, Jonathan Rauch argues that the decline of political parties is a major cause of America's hyperpartisanship and political gridlock, and that these problems can be at least partly remedied by re-strengthening parties and "middlemen."
Two decades ago, Rauch wrote a book, Demosclerosis, arguing that there were so many organized interest groups that they cancelled each other out and produced political gridlock. Now he adds the disempowering of parties to the mix, along with public anger at seeing the ineffective mess in Washington. I think there are several other causes of political dysfunction -- court decisions, gerrymandering, a part-time, reelection-focused Congress -- but Rauch is right about the weakness of political parties and their inability to reward responsible behavior.
The voters are a problem, too, because they prefer one-sided policy victories rather than compromises. But it would help to bring back earmarks in spending bills and the "regular order" in lawmaking.