By 2012, results in the House of Representatives were so skewed that the Republicans comfortably maintained their majority despite the fact that Democrat candidates received more than 1 million more votes. Take Pennsylvania, where Democrats won nearly 51 per cent of the vote, but Republicans won 13 seats to five. Or Michigan, where the Democrat vote was nearly 53 per cent while Republicans took almost twice as many seats. North Carolina: 51-49 to the Democrats but nine Republican seats to four. And on it goes. That sort of result landed in at least 10 states - only one of which was rigged to favour the Democrats. To get a sense of the scale of it, consider that in the seven states redrawn by Republicans, near parity voting (16.7 million votes to 16.4 million) delivered 73 Republicans and 34 Democrats.

That's a clear perversion of democracy, and it's no accident. The Republican State Leadership Committee made it explicit. It ran a $30 million project called Redmap, aimed at winning key seats at the state level which would give it the power to draw electoral boundaries. What's more, it planned to do this in a census year so it could draw with precision - 2010 was exactly such a year.

So the plan worked. The Republicans played the system. But now the system is playing them. Sure, Republicans look set to control the house well into the future. But in the American system, the political contest doesn't simply vanish. It shifts to the primaries. Now if you're a Republican house member, your greatest threat comes not from Democrats, but from other Republican challengers hungry for your seat. The result is that Republicans are talking more to their own base, and less to everyone else.

Old school Republicans might shake their heads at the rising rabidity of their Tea Party colleagues, but the truth is they're presently no match for them. The last thing an aspiring congressional Republican needs is a well-funded lobby group running campaigns lacerating them as closet socialists prepared to deal with a rampantly socialist Obama. Freed from the need to defeat any meaningful Democrat challenge, Republican politics is now such that everyone's racing to outbid each other for the mantle of true believer.

It's a classic case of a closed system encouraging ever more radical posturing.