Dick Cheney’s in a spot of bother again. He hasn’t shot anyone this time. It’s not his wayward aim with a 28-gauge shotgun that’s in the news, but his deadly accuracy with a nine-point legal memo.

The US Vice-President has been refusing to comply with a fairly routine internal government supervisory process designed to determine how official information should be classified and declassified. His lawyers have said he will not submit documents to the National Archives on the ground that, since the US Constitution makes the Vice-President part of both the executive branch and, per his role as president of the Senate, the legislative branch of government, and since the two are supposed to be separate, he can’t really be part of either, and therefore can’t be subject to the usual legal obligations.

It is a splendid piece of legalistic legerdemain, the sort that makes lawyers want to hug themselves in self-appreciation and do victory laps around a bamboozled courtroom. But it is, as even Mr Cheney’s remaining admirers (Mr and Mrs Hiram Z. Quailshooter of Jackson, Mississippi) have acknowledged, a tad breathtaking in its audacity.

Its import is, quite literally, that the Vice-President gets to ignore the law because he is his own special branch of government, not defined by the Constitution, The French used to have a term for this idea: “L’état, c’est moi.” Sadly, for fans of 18th-century absolutist monarchy, Mr Cheney’s daring bid at a Restoration didn’t last. Yesterday, an evidently unpersuaded White House dropped the extra-constitutional claim, though it still said there were other reasons for Mr Cheney not to comply.

But the episode was instructive. The Vice-President is the focus of considerable attention at the moment. The Washington Postpublished this week one of those 100,000 word series so beloved by the American press (Is there any more disheartening phrase in the English language than “first in a four-part series”?) that lovingly documented Mr Cheney’s central role in the big decisions of the Bush Administration, from the legal status of detainees in the War on Terror to torture and energy policy.

This latest episode over the National Archives provides a fascinating insight into how Mr Cheney has developed his role over the past six and a half years. Before Mr Cheney, the vice-presidency was famously an empty job. He would attend funerals of foreign dignitaries, throw out the ceremonial first pitch at baseball games; and, if he was really lucky, get to head a task force on issues such as harnessing energy from the Aurora Borealis.

But the current incumbent has been something else. He has actually used the very vagueness and general ethereality of the vice-president’s role and turned it into the freedom to roam the institutions of American government untrammelled by legal or political constraints and always in total secrecy.

He has, to use the infamous description of the vice-president’s role by one of his predecessors, taken the pitcher of warm spit and turned it into a vial of liquid kryptonite. All of which merely underlines that it is high time that America had a serious discussion about the way it chooses its vice-president.

The country is in the early stages of the longest presidential campaign in history. It will have cost, when a winner is eventually declared, upwards of a billion dollars and will have involved the direct participation of well over a hundred million people in repeated ballots. Every candidate – even the nutters and the no-hopers – will have had every last wart and polyp examined in excruciating detail by the media.

But when it comes to picking the vice-president, the task will be delegated to one person – the presidential nominee of each party, who after a week or two of desultory deliberation, will pick some smiling nobody on the ground that he or she may just pull a state or two into the presidential candidate’s column.

And yet the vice-presidency has been an important job in America, long before Dick Cheney used it to become the Dr Strangelove of the Bush Administration. Even if the next veep goes back to being, as I suspect he may, the mourner-in-chief at African leaders’ funerals, he will still be of large political consequence.

This is not because of what he does but because of what he usually becomes. The vice-presidency is the very best spot from which to run for the presidency. In the past 50 years, every single vice-president who has later sought his party’s nomination for the presidency – with one exception – has got it: from Richard Nixon to Al Gore, by way of Lyndon Johnson, Hubert Humphrey, Gerald Ford, Walter Mondale and the first George Bush. The exception was Dan Quayle. While most of these had distinguished careers before the vice-presidency, it was clearly getting the No 2 job that propelled them to the presidency.

I can think of no better illustration of the phenomenon and its implications than the current president. Why, really, is George Bush now President of the US? Certainly, he had been an effective Governor of Texas, but the main reason he got a start in politics was because his father had been President. And why was his father President? Largely because he had been Ronald Reagan’s Vice-President.

Mr Bush Sr only got on the Republican ticket in 1980 because of a last-minute change of heart by Mr Reagan. He had been planning to announce that his No 2 would be Gerald Ford, the former President. But his advisers were not convinced and in frantic, last-minute discussions at his Detroit hotel, he was dissuaded.

Suddenly needing a new nominee, his advisers lighted on George Bush, Mr Reagan’s losing opponent in the primaries that year. They summoned him at three o’clock in the morning, and the rest, as they say, is history. That decision in a Detroit hotel room produced in effect, three presidential terms – one for Mr Bush Sr, and two for his son.

The US presidential election process is, for all its faults, a terrifically exhaustive way to select the leader of the world’s most powerful country. The vice-presidential selection process? Not so much.

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