The establishment is the 3rd party

What seems to be emerging, or wants to emerge, is a 3-party system. On the left and right wings we have populist movements, and in the center the establishment moderates. In such a scenario, the Tea Party/Trump crowd is a nationalist voting block, the Occupy/Sanders crowd is basically a Democrat-Socialist party. The center party would cover the current Democrat-Republican barrier, and include politicians like Jeb Bush and Hillary Clinton, and probably Barrack Obama.

Will that actually happen? Generally the two-party system is quite stable. And on the left we see the stabilization in action with Hillary constantly moving towards Bernie's positions. So far I haven't heard many Bernie supporters saying they'd refuse to vote for Hillary. They'll rally around her in opposition to Trump or basically whoever the Republican candidate is. So Bernie will have had the effect of shifting her campaign rhetoric, although that's no likely to matter to much once she's elected. So a lot of people on the left will be pissed off, but they'll toe the line and the party will be stable. The system is stable because everyone votes against the other guy.

The Republican party though, is not quite as stable. We saw it several elections ago when Ross Perot split the right vote. We saw major conflicts in the Republican caucuses during the Ron Paul campaigns. And now Trump threatens to split the party apart. And the reason, to me, is simple. The party has two camps: the conservative, nationalist part, and the part that represents the corporate, financial, and globalist interests. The two are increasingly at odds with one another. I think it's only a matter of time until the party splits.

Now, if you're a Democrat, particularly a liberal one, you're probably giddy with excitement at the prospect of the GOP crumbling. Don't be. You can't just destabilize one half of the system. The effects will trickle throughout. What happens to the establishment part of the GOP when Trump wins the nomination, or takes a large chunk of the voting block with him for an independent run? Those people who support Rubio or Bush could probably come over and support a Clinton or Biden, or any centrist establishment Democrat versus Trump. At the least, you'll see a lot of that corporate lobbying move towards Democrats. This will alienate the anti-establishment liberals even more, and would ultimately cause the Democrats to fracture as well.