The underlying cause is a mistake of our founding fathers. Because of the winner-take-all structure of our elections, our political parties are forced to be forkophobic. The fact that we can't have a real Tea Party, to say nothing of the Greens and Libertarians, causes our civil war proclivities.
A first step is a proportional House. In this proposal, every state stops drawing House districts, which also kills gerrymandering (although gerrymandering by itself does not cause our civil war problems). Instead, parties must register with the state with a list of N names, people in the state vote for the party rather than an individual, and after the election we first off exclude any parties who have not gotten at least 4% of the vote, then allocate the rest by the Webster method that we already use to allocate House seats among the different states. So a party has 10% popularity in California, that means they receive about five California seats, so the top five names off their pre-published California list go on to the House. Forking a political party is now possible, politicians have spines again at least in the House, and Washington starts working again, hopefully.
This probably does not require a constitutional amendment, just a federal law.
