from Bring Back Political Parties by Kevin Williamson at National Review :
As it turns out, political parties are — like churches, civic groups, unions, trade groups, lobbyists, pressure groups, and business associations — part of the secret sauce of civil society. In much the same way as our senators — in their original, unelected role — were expected to provide a sober brake on the passions of the members of the more democratic House of Representatives, political parties exercised a soft veto that helped to keep extremism and demagoguery in check. Anybody can run for president — but not just anybody can run as the candidate of the Republican party or the Democratic party. Third parties face an uphill battle, but that doesn’t mean that they cannot prevail: The Republican party was a very successful third party, displacing the moribund Whigs.
The denuded political parties provide an important fund-raising and administrative apparatus — along with a tribal identity that is arguably more important — but they do not offer much more than that. Instead, we have relatively little in the way of mediating institutions between candidates and the public at large. If Donald Trump and Bernie Sanders are your idea of great political leaders, then you probably don’t see a problem with that. You’re a fool, but you’re a fool who is likely to get his way in the coming years. The difference between a republic and a democracy is that republics put up more roadblocks between fools and their desires.
The project to make the Democratic party an instrument of the Clinton campaign in order to prevent Bernie Sanders from making it an instrument of his own ambitions was dishonest, corrupt, and possibly illegal.
It was also exactly what political parties are supposed to do. A little democracy, like a little whiskey, is a good thing — too much and you end up with Ted Kennedy.