Charles does a good job of explaining why our representative democracies in the west seem to have all become bland, indistinguishable minor variants of one another:

For a while I’ve had the unwelcome feeling that we’re living under occupation by Martian invaders. (Not just here in the UK, but everyone, everywhere on the planet.) Something has gone wrong with our political processes, on a global scale. But what? It’s obviously subtle — we haven’t been on the receiving end of a bunch of jack-booted fascists or their communist equivalents organizing putsches. But we’ve somehow slid into a developed-world global-scale quasi-police state, with drone strikes and extraordinary rendition and unquestioned but insane austerity policies being rammed down our throats, government services being outsourced, peaceful protesters being pepper-sprayed, tased, or even killed, police spying on political dissidents becoming normal, and so on. What’s happening?

Here’s a hypothesis: Representative democracy is what’s happening. Unfortunately, democracy is broken. There’s a hidden failure mode, we’ve landed in it, and we probably won’t be able to vote ourselves out of it.

[. . .] Parties are bureaucratic institutions with the usual power dynamic of self-preservation, as per Michels’s iron law of oligarchy: the purpose of the organization is to (a) continue to exist, and (b) to gain and hold power. We can see this in Scotland with the SNP (Scottish National Party) — originally founded with the goal of obtaining independence for Scotland and then disbanding, the disbanding bit is now nowhere to be seen in their constitution.

Per Michels, political parties have an unspoken survival drive. And they act as filters on the pool of available candidates. You can’t easily run for election — especially at national level — unless you get a party’s support, with the activists and election agents and assistance and funding that goes with it. (Or you can, but you then have to build your own machinery.) Existing incumbent representatives have an incentive to weed out potential candidates who are loose cannons and might jeopardize their ability to win re-election and maintain a career. Parties therefore tend to be self-stabilizing.

[. . .]

So, here’s my hypothesis:

• Institutional survival pressure within organizations — namely political parties — causes them to systematically ignore or repel candidates for political office who are disinclined to support the status quo or who don’t conform to the dominant paradigm in the practice of politics.
• The status quo has emerged by consensus between politicians of opposite parties, who have converged on a set of policies that they deem least likely to lose them an election — whether by generating media hostility, corporate/business sector hostility, or by provoking public hostility. In other words, the status quo isn’t an explicit ideology, it’s the combined set of policies that were historically least likely to rock the boat (for such boat-rocking is evaluated in Bayesian terms — “did this policy get some poor bastard kicked in the nuts at the last election? If so, it’s off the table”).
• The news cycle is dominated by large media organizations and the interests of the corporate sector. While moral panics serve a useful function in alienating or enraging the public against a representative or party who have become inconveniently uncooperative, for the most part a climate of apathetic disengagement is preferred — why get involved when trustworthy, reassuringly beige nobodies can do a safe job of looking after us?
• The range of choices available at the democratic buffet table have therefore narrowed until they’re indistinguishable. (“You can have Chicken Kiev, Chicken Chasseur, or Chicken Korma.” “But I’m vegan!”) Indeed, we have about as much choice as citizens in any one-party state used to have.
• Protests against the range of choices available have become conflated with protests against the constitutional framework, i.e. dissent has been perceived as subversion/treason.
• Occasionally cultural shifts take place: over decades, they sometimes reach a level of popular consensus that, when not opposed by corporate stakeholders, leads to actual change. Marriage equality is a fundamentally socially conservative issue, but reflects the long-term reduction in prejudice against non-heteronormative groups. Nobody (except moral entrepreneurs attempting to build a platform among various reactionary religious institutions) stands to lose money or status by permitting it, so it gets the nod. Decriminalization of drug use, on the other hand, would be catastrophic for the budget of policing organizations and the prison-industrial complex: it might be popular in some circles, but the people who count the money won’t let it pass without a fight.

Overall, the nature of the problem seems to be that our representative democratic institutions have been captured by meta-institutions that implement the iron law of oligarchy by systematically reducing the risk of change.

It’s not just your imagination that the last presidential election hinged far more on trivia than on actual policy differences — because Mitt Romney was offering only a slight variation of policy choices than what Barack Obama had been doing (heated rhetoric and animated posturing aside). “Conservatives” and “Liberals” in Canada became almost interchangeable (except on foreign policy and military matters). “Conservatives” and “Liberal Democrats” have been able to form and hold a coalition government together in the UK relatively amicably (once again, aside from the meaningless noise and fury at the margins).

Party politics requires parties that want to achieve power to more closely resemble the party that already holds power (look at Canada’s NDP for evidence of that: the more similar to the Liberal party they became, the more popular they became, to the point they completely eclipsed the Liberals in the last federal election).