As we watch figures like Palin and Bachmann and Beck and Hannity define contemporary Republicanism, the gulf between the GOP and the British Tories has widened to a chasm. Gideon Rachman wonders what could happen if Cameron wins:

Like many youngish politicians, Mr Cameron would dearly love to embrace President Barack Obama and to drink deeply from his aura – if such a thing is possible. But the Tory leader has to pretend that the US politicians he is closest too are the likes of Mitt Romney, Newt Gingrich and Sarah Palin.

This is a pretense that is increasingly painful.

The special relationship between Mrs Thatcher and Ronald Reagan was based on a genuine meeting of minds. The two leaders shared core beliefs in anti-communism and small government. But, since then, the Republicans have moved right and the Tories have moved left. The Republican party has just made it clear that it regards state-run healthcare as on a par with Satanism. But Mr Cameron tells British voters that he treasures the National Health Service. Only last week, the Tory leader gave a speech on community organisation in which he explicitly praised the late Saul Alinsky – a Chicago-based social organiser who is a bogeyman for many Republicans, who regard him as Mr Obama’s socialist Godfather.

From guns to God to taxes to climate change, the Tories and the Republicans are really no longer on the same political planet. This problem would become far more acute if a Tory victory in Britain next month was followed by a sweeping Republican victory in the mid-term congressional elections in November. Who exactly would a Prime Minister Cameron side with when political war broke out on the other side of the Atlantic? His political allies in Congress or his political hero in the White House?

One aspect of contemporary Toryism is its coolness toward the US-UK special relationship. The Bush years took their toll on Britain too and the war in Afghanistan is deeply unpopular.

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