Was the US ever faced with simpler choices than it is on this Super Tuesday? The country is fighting two wars against a Muslim enemy that is spreading rapidly across the world, both culturally and demographically, and with a major terrorist event in the US possible at any time. The American economy is meanwhile facing a recession at best, Armageddon at medium, and the third circle of hell at worst.

Moreover, the US is host to tens of millions of illegal immigrants whose presence will become more than irksome as job losses mount. In other words, Pearl Harbour and the Wall Street crash on the same week, sort of.

Now why anyone would want to take control of the ship just as it heads into an ice-hurricane off Cape Horn is one of the mysteries of politics. For the political ambition is one of the great dividing characteristics within mankind. Those of us outside its gravitational pull do not understand the almost irresistible command that it exercises over its almost hapless votaries.

For no-one enters political life for virtuous reasons. No-one.

Politicians become politicians because they want power, and because they want celebrity. Self, not honour, drives politics, whether the arena is a parish council or the US Congress, and there's no point on complaining about it. Somebody has to collect the garbage, and somebody has to run politics: both are necessary in a civilised state, even though the perpetrator of each is curiously indifferent to the appalling vocational smells they live with.

Looking for modest virtue in a politician is like choosing a tank-commander because he is a vegan. All politicians are show-offs who are addicted to cameras, to committee-meetings, to deals, to the control of power, and the relegation of the family to their careers.

All politicians are damaged people, who -- paradoxically -- display their disabilities and infirmities as proof of their capacity to do the job.

So in one sense the US presidential race is a competition between cripples: all of the candidates are suffering from personal defects that disqualify them from membership of respectable society. Politics is, in effect, run by a caste of untouchables, which is just fine.

We're not inviting them to have sex with us, but to do a job. Therefore, the only question is this: what untouchable do you want on the bridge as the vessel rounds Cape Horn, to face into The Perfect Storm? I mean "you" in a very literal, rather than in a loose grammatical sense, for we are an extension of the US economy. We may not have the vote, but the outcome of the election is nearly as vital for us as it is for the people of Maine or Rhode Island.

Now choosing a candidate because she is a woman is as sensible as choosing your brain-surgeon merely on grounds of vulva-ownership. Or you can vote according to race, which is as prudent as selecting a fireman to save your burning house because his grandfather hunted with spears. Or you can choose someone merely because he has been a prisoner of war: by which principle, Clive Dunn, who played Corporal Jones in Dad's Army, and who was a POW between 1941-45, is your ideal candidate. Or you can vote for a Mormon nonentity because now is the hour of Mormon nonentities.

But having said that I don't expect a sense of honour amongst politicians, when one of them has unassailably shown that he has this quality, and was even prepared to give his life in its defence, then he is clearly in a class apart. That is John McCain, who as a POW in North Vietnam actually refused early release, which had been offered to him because his father was a US admiral. But Navy Lieutenant McCain insisted that prisoners captured before him should be released before him. His reward for that extraordinary courage was to be tortured nearly to death. So he has to be the Republican candidate. Any other decision would be insane.

Then we come to the Democrats. Well, frankly, I would vote for Donald Duck in preference to Hillary Clinton, whose raw and unprincipled ambition is such that it glows in the dark, like plutonium reaching critical mass. In her ravening covetousness, she once said that she was named after the conqueror of Everest (no, not Tensing), in order to embody his courage and tenacity: but in fact, she was born six years before Edmund Hillary achieved that feat.

The idea of such a worthless creature, aided by her even more abominable husband, running the wars of cultural survival in Iraq and Afghanistan (which is what they have become, of which more on another day), and managing an economy in recession, is too terrifying for words.

So, may the Democrats plump for Barack Obama, and thereby finally rid the US polity of the Clinton toxins. Obama is a clever fellow, and will go far: a President, perhaps, in eight years' time.

But this November, as the great storms approach, there is only man to have on the bridge: US Navy Captain John McCain, Silver Star, Bronze Star, Legion of Merit, Distinguished Flying Cross, and Purple Heart. No contest.