Over the past week there have been a number of articles dealing with the question of why President Thabo Mbeki has so loyally backed his sickly Minister of Health, Manto Tshabalala-Msimang.

The contrast with Mbeki's ruthless dismissal, on contrived charges, of her independent-minded deputy, Nozizwe Madlala-Routledge, has attracted a great deal of adverse comment. A few weeks ago the Economist editorialised that Mbeki had "rid himself of the wrong health minister."

Even formerly sympathetic Western commentators have now turned against Mbeki. In reaction to this controversy the British journalist John Carlin - once an outspoken admirer of the ANC leadership - has described Mbeki as a strong candidate "to rank, with his friend Robert Mugabe, among the worst Presidents in the world."

So far a number of explanations have been proffered. In a defence of his minister published last week Mbeki noted that he and Tshabalala-Msimang go back a long way. "I went into exile with her, in 1962, when we, young adherents of the ANC and militants of the national liberation movement, obeyed the command of the ANC to go abroad to study."

Other articles have pointed out that the minister is married to the powerful ANC treasurer-general, Mendi Msimang; and that her controversial views on "HIV and AIDS" simply reflect those of her boss. As Mark Gevisser told the Sunday Times, "My sense is that she articulates [Mbeki's] perspective on HIV/Aids."

Yet to note their obvious sense of loyalty to each other, only takes the explanation so far. Mbeki is not a sentimental politician, and the question really is why he sees it as being in his interests to retain Tshabalala-Msimang in the health portfolio?

A useful way of looking at the Mbeki-Manto bond is as a patron-client relationship. This has been an "important structuring element" of Mbeki's rule, as it was in the old Soviet-bloc.

For instance, T.H. Rigby writes that in the Soviet Union Stalin was the "unquestioned ‘boss', his lieutenants entirely dependent on his personal favour, each of them striving meanwhile to build up his own network of followers, while Stalin in turn depended on them to administer the spheres entrusted to them in accordance with his wishes." Rigby continues:

"Such reciprocal dependence is the core of the patron-client relationship, however unequal their power resources may be, and its corollary is a high degree of objective loyalty between the parties to it, whatever their secret feelings. The follower must never act against the boss's interests, and must be ever ready to put his hand in the fire for him, if required, while the boss must maintain and protect him, so long as he does so act."

Such relationships have been characteristic of Mbeki's style of rule. The way in which he extended his control over party and state was to centralise control over appointments and then elevate loyalists to key positions.

Back in November 1998 Robert Schrire wrote that political loyalty was the "most important factor in determining recruitment to the Mbeki team. This in turn requires personalities and intellects who constitute no threat to the leader personally."

He also observed the mutual dependence between Mbeki and his courtiers. "While his aides clearly are dependent upon Mbeki's continued favour for their positions, the leader too becomes increasingly dependent upon his staff to make the system work."

Even the ministers who are in the cabinet on merit have been required (or felt obliged) to put their hand in the fire for Mbeki, on occasion. The most recent example of this was Finance Minister Trevor Manuel's disingenuous defence of Mbeki's morally squalid Zimbabwe policy.

Tshabalala-Msimang's rapid rise through government ranks certainly owes something to her pliability. In early 1996 she was the chairman of the parliamentary portfolio committee on health. The then Minister of Health Nkosazana Zuma was, at that time, in a great of trouble over the spending of R14-million on the Sarafina 2 play.

After the scandal broke Tshabalala-Msimang's first instincts were to try and do the right thing. In reply to a comment from the health department that no taxpayer money had been spent on the play (it had come from the European Union) she stated that, "it does not matter where the money came from. It is for the development of this country and it should be used wisely." Zuma, and her director-general Olive Shisana, were summoned in mid-February 1996 to appear before the committee.

However, these hearings were scuppered after the presidency intervened, and Tshabalala was instructed to drop the matter. When the hearings were eventually re-convened at the end of the month it was clear the ANC caucus on the committee had been whipped into line

Indeed, in a key parliamentary debate on the scandal which followed Tshabalala was the one who proposed a motion which said that Zuma had given a "satisfactory and detailed report" at the meeting, and expressed "its confidence in the Minister."

Tshabala-Msimang's reward for her about-turn came a few months later when she was appointed as deputy minister of justice. The Hogarth column in the Sunday Times noted that this was an unexpected appointment, as she had "little legal experience and a low profile in Parliament." It continued:

"She did, however, have one moment in the spotlight this year, when she had a chance to grill Dr Nkosazana Zuma about the spending of R14-million on the Sarafina 2 play. Before the [committee] meeting President Nelson Mandela met Ms Tshabalala. What transpired at the meeting is not known, but the result was a pliant committee meeting which acted more as a smokescreen than an example of openness and transparency. Now, the show of loyalty seems to have paid off. Democracy's loss is her gain."

At this time Mendi Msimang was the South African high commissioner to London, and not yet the powerful figure he would become inside the ANC.

Something very similar happened after Manto-Tshabalala-Msimang was promoted Minister of Health in June 1999. In the final period of her period as health minister Zuma had come under a great deal of pressure to reverse the decision, taken in October 1998, to block the provision of AZT for the prevention of mother-to-child transmission.

At the time Tshabalala-Msimang took office the government line was that AZT was simply too expensive. Although she parroted this view, she did make clear that she had an open mind on the matter, and (initially) did look for cheaper alternatives. In late July 1999 The Star reported that Tshabalala-Msimang "will lead a delegation to Uganda next week to investigate the inexpensive HIV drug nevirapine, which can prevent mothers from infecting their babies at birth."

It was from late October that year that Mbeki began his descent into AIDS ‘denialism.' Tshabalala-Msimang followed, but some way behind. As Gevisser notes, "It is clear that she didn't come into the job as a sceptic, but has been clearly educated or influenced by her engagement with Mbeki."

On this issue she was not only required to put her hand in the fire for Mbeki, she had to hold it there. She has made herself, on Mbeki's behalf, a figure of international ridicule and loathing. The strain for someone who is a very ordinary person must have been immense. It is little wonder that she became increasingly tired and emotional. In this context, the least Mbeki could have done, after she fell seriously ill, was to intervene to expedite her liver transplant.

This form of rule has not been conducive to effective governance. As was the case in the Soviet Union, ‘loyal cadres' who mess up are generally kept in their jobs, or moved to others. The dangers for Mbeki of failing to "maintain and protect" his followers is well-illustrated by the consequences of his falling-out with his once loyal no. 2, Jacob Zuma.

Rigby notes, "A power structure built on patron-client relationships is viable only as long as each side's expectations of the others loyal behaviour is generally confirmed by experience."

At some point between 2000 and 2001 the two men's "expectations of the other's loyal behaviour" began to break down.

It is not clear who was to blame for this. As noted in an earlier article in late 2000 Zuma was perceived to have acted against Mbeki's interests by allowing parliament to launch the arms deal inquiry. In retaliation Mbeki seems to have withdrawn Zuma's protection, and allowed him to be indirectly investigated.

Whatever was left of their sense of mutual dependence by mid-2005 was finally exploded when Zuma was sacked and charged with corruption. The unravelling of Mbeki's tight hold over the ANC was largely precipitated by Zuma's subsequent rebellion.

Zuma himself was motivated by an intense - and in the context of the patron client relationship, understandable - sense of betrayal. He also took his own network of followers with him. There was also a broader perception within the ANC that Mbeki had broken certain unwritten rules. If Zuma was not protected, then no-one was safe.