In politics, as in life, there are some things you notice only when they are gone. One of them is the will to govern.

The will to govern is an intangible political asset, and is therefore difficult to identify and describe. That's why it's easier to see it when it isn't there. Without it a political party has little chances of success. Without it a party is even in danger of wasting away completely. And since it is not easily apprehended, it is easily lost.

These may sound like adventurous claims, and rather abstract. They are neither.

South Africa has, in its recent political history, seen so vivid an illustration of these truths that it astonished the world. It may be about to see another.

It happened when the National Party, the party of apartheid, undertook - in the words of a wit - "an about-turn in mid-goosestep". The Nats liberated the country's liberation movements and set about drawing them into a home-based process of negotiation.

Despite the witty image, this didn't really happen suddenly. The once-monolithic party's bedrock of self-belief had been chipping and splintering for some while. First the intellectuals of Afrikanerdom lost the faith, then the business elite. Finally, the new leader, F W de Klerk, moved by causes still not fully explained, pulled away the gauze curtain to reveal the future that everyone could already see in outline.

When the judges of history make their final ruling on whether the white nationalists underwent a change of conviction, or simply tired of the futility of holding up the crumbling edifice, the judges will very likely rule: a bit of the former and quite a lot of the latter.

Wherever the emphasis comes to rest, the central fact will tower over the affair. The Nats had admitted: we were wrong.

A party does not lose its will to power precipitously; it's something that, first, corrodes then ebbs away over a period. It is also so that the party and its members are often the last to recognise the changes to their collective psyche. Accordingly, the National Party coddled the self-reassuring illusion, after its big switch-around, that it would be able to bamboozle the ANC and its communist and trades union fellow travellers into a power-sharing partnership. This would be an arrangement in which the white nationalists would, through dint of their superior political skills, effectively exercise power - even if it meant steering from the backseat.

That's not what happened. Their skills weren't superior. But, more importantly, once the Nats had admitted that they had been wrong all along, they lost the moral base for their will to govern. They entered the negotiations, in effect, to negotiate the terms of their surrender. Deep down, they knew they didn't have a leg to stand on. (It is worth noting that the term "surrender" was the one most frequently resorted to by the NP's critics both within and outside the party ... and a view often taken by commentators.)

In the event, the power-sharing deal was still-born, and the party all but withered away.

Along the way, though, it provided a text-book example of the origins and the death of the political will. The will to govern is a function of self-belief. A leader and those he leads must have self-belief in order to convey their conviction to others, and get those others to suborn their own, individual will to that of the leader and the group. And the conviction and self-belief arise, in turn, from holding a moral position.

It may seem strange to speak of the party of apartheid and a moral position in the same breath. The fact is that the working of the psyche, both individual and collective, especially collective, is such that it need not be a good moral position. It need only be a moral position. History harbours a sombre catalogue of people whose moral positions were abominable, but whose Nietzschean will carried them to domination. As Yeats had it: "The best lack all conviction, while the worst / Are full of passionate intensity".

The dynamic was seen at work again this weekend, this time in Britain. The Conservative Party (Tories) had been riding high, partly on the woes of the Prime Minister, Gordon Brown, and partly on a rediscovered sense of self-belief, and a commensurate ability to spread that self-belief into the electorate.

Then came the credit crunch. While Mr Brown plodded on, crafting a rescue package that the rest of the world gratefully imitated, the party of supposed financial competence, the Tories, stood rooted to the spot, its collective mouth opening and closing every now again, without any meaningful sound coming out. To make things worse, it turned out that as this situation was percolating, and the politicians took their summer holidays, Mr Brown was in a cottage at Southwold on the English coast, taking walks along the beach in a sports coat, hard shoes and dark trousers. The Tory silver-spooners, by contrast, were in espadrilles and white slacks (I imagine) lolling in Mediterranean villas and aboard the yachts and private jets of shady billionaires, talking big bucks.

These were not bucks they should have been talking about, it was soon revealed. Thus, in a society where class divisions have substantially dissolved - yet remain die-cast in the minds of people - the Tories had sunk a dagger deep into their own chest.

Others gleefully unsheathed their blades and joined the stab fest - even the Tory faithful, which was strange. But strange only until the high priest of Tory commentators explained in The Telegraph on Saturday that "if the Tories had been confident about their party's direction" they would have defended their chief loller-in-villas. They didn't because they couldn't. The Tories knew they had failed. Instead, wrote Charles Moore, "we sensed Tory weakness so pushed the tale for more than it was worth".

So there it is again: lack of self-belief equals corrosion from within, equals messages of weakness to the outside, equals the baying of the hounds for the kill.

A final example of the supremacy of the will in the armoury of politics: the presidential election in the United States. Obama sensed early on that change is the leitmotif of America now, and knows, deeply knows, that he is its agent. Whereas McCain, as the candidate of the incumbent Republican Party, cannot shake the image of representing a failed political project. Nowhere was this more evident than the presidential debates. Obama floated just above the fray, smiling benignly as his opponent hunkered down to lunge and slash.

So, the issue is: how do questions of the will, critical as it is, apply to the ANC?

Is there an old ANC, genuine and true, ongoing and faithful to its founding ideals? And is this pristine ANC the invincible custodian of the movement's will to govern?

There are good reasons to hesitate over the answer.

It seems beyond dispute that the core of the ANC has been corroded by corruption, by greed, and by expediency. Only the extent allows for argument, not the fact.

Do the old stalwarts, among whom there are many fine and honourable souls, not know and acknowledge this in their heart of hearts? Do they not bleed in the name of the cause for which they sacrificed so much?

Are they not galled by the cynicism of employing Jacob Zuma, first as a kierie to cosh the former leadership, then as a catalytic medium to try to bind the already-fracturing party together, knowing all the while that he is not a true leader with true leadership qualities and vision? That he is, rather, seen as the very personification, correctly so or not, of the corruption and greed that has been corroding the party's spirit?

Is it not this underlying disquiet of the conscience that Lekota, Shilowa and their fellow splinterists are struggling to articulate when they talk about the ANC losing its way, about straying from the Freedom Charter and about betraying its constitution? About the ANC losing its character, heart and soul? Are they not, in fact, trying to voice a deep and shared belief that the ANC is no longer capable of believing with honesty in itself?

If these are valid questions, then one of the key notions in them is carried by the word "shared" in the previous paragraph. To a large or lesser degree the loss of belief has infected, and is infecting, both those who have left the party, and those who are hanging in.

This is a well-observed phenomenon, going back to the medieval monasteries. When a monk's spirit decayed, and he declared all about him to be unwholesome and corrupt, causing him to take his mug and mat and leave, he left behind him the other monks wondering if he didn't have a point. In this way corrosion of belief would set in.

This has already happened, in print, with one prominent hanger-in, Ronnie Kasrils, circumspectly suggesting in a recent article that the leavers may have some valid gripes.

If this sapping of the capacity for self-belief continues - and why wouldn't it? - we must ask who will be the inheritors of the will to govern? Who will come out of the present, churning, reformation of South African politics with the unalloyed self-belief that will drive them to power?

Stanley Uys has recently written about the rise to dominance of the South African Communist Party (see here). His observations are acute, and the orb of Nietzsche is clear, in part at the very least, passing to the thinkers and activists in the SACP. Moreover, the greatest single argument against them - that they were out of step with history - has just been badly damaged. The crisis of capitalism has everywhere in the world realigned thinking in this respect.

The communists believe unshakably that they are the instruments of history. They are moved by the conviction that their ideology is not only necessary, but pre-ordained.

At the other emerging pole of South African politics the splinterists see themselves as the caretakers of the original soul of the ANC. One might easily scoff at this, since they will probably have neither the power nor the numbers ... were it not for the fatal, will-draining damage the core ANC is unstoppably inflicting on itself.

This means, then, that the fervent apparatchiks of the left, one the one hand, and the old souls of the liberation movement's honour-guard on the other, could become the polarities of South African politics in the future.

Those whose sweaty present grip on the levers of power is slipping may ultimately be squeezed out - because they know, they know ... in the lonely hours of the night when the righteous sleep, that they are there only to milk the cow of state.

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