Ministerial resignations arise for unique reasons and yet wider lessons are always sought and sometimes learnt. In the case of Liam Fox, the hunt for lessons focuses on the role of lobbyists and the relationship between ministers and their senior officials. For David Cameron, these themes are conveniently apolitical. You can bet the price of your next gas bill that Cameron will act, or be seen to be acting, by drawing up tougher rules for lobbyists as he had once pledged to do.

Yet these are the least important lessons to learn from the Fox saga. It is precisely in these areas, his relations with senior officials and the access given to a favoured friend, that Fox was unique. In yesterday's Independent, Mary Ann Sieghart described in illuminating detail the former Defence Secretary's lofty attitude towards his Permanent Under Secretary, Ursula Brennan. Sieghart reports that Fox often ignored her at meetings and bypassed her warnings about his friend, Adam Werritty.

This is unusual. Mostly cabinet ministers are either in awe of senior officials or are at least eager to please. Quite often they lose all control of their time as they dance to ill-considered schedules drawn up by officials. Most senior officials prefer such subservience to assertiveness. One reason Gordon Brown and Ed Balls were unpopular with parts of the Treasury was that they arrived with their own ideas and were determined not to succumb to the conservative orthodoxies that permeate the mighty department. Fox's self-confidence had a positive side, too, in that he was to some extent getting to grips with one of the most inefficient departments in Whitehall. The same rare ministerial arrogance also led to a level of risk-taking that was bizarre.

But it would be wrong to conclude from this saga that senior officials must have more control over ministers. They have more than enough already. Fox might have been out of control, but most of them are not. Those that are do not last very long. Look at what has happened to Fox.

The lack of ministerial staying power is one of the reasons why lobbyists are not as influential as they seem. Think of all those lobbyists who had cultivated the former Transport Secretary, Philip Hammond, in the hope of gaining access and information in relation to everything from high speed rail to bus services. Hammond's attentions are now focused on military matters and will no longer relate to how people stagger around on Britain's fractured transport network.

On the basis of the previous pattern, his successor, Justine Greening, will not be there long either and yet lobbyists will seek near meaningless access and insight as she acquires a fleeting interest in transport before moving on. Probably Hammond will not be at Defence for more than a year. Evidently, he is seen as a "safe pair of hands" and, in this government of curious personalities, will be required elsewhere fairly soon. Tony Blair regarded John Reid as similarly dependable. Reid rarely stayed at one department for more than 12 months. Whether he was a safe pair of hands is another matter, but lobbyists were wasting their time with him. He was gone before he could have much impact on policy.

Indeed Derek Draper was telling the truth when he was caught during Blair's first term boasting in his new role as a lobbyist that only a handful of people mattered in the Labour government and he knew them all. This did not stop an army of lobbyists queueing up for the attention of other ministers in an administration when Blair, Brown and their closest advisers micro-managed every department. The lobbyists' hyperactivity was only sinister in theory. Even if they acquired access, most ministers would proceed to do what Blair or Brown told them to do irrespective of the most arduous lobbying.

Famously, David Cameron takes a different approach to leadership. He is so laid back he did not seem to know what Fox was getting up to. This is not especially surprising given that, apparently, he did not know what was in Andrew Lansley's original White Paper on the NHS, an excuse that remains almost unbelievable. I still hope the alternative explanation is true, that he did know what was in the White Paper and agreed with it, an alarming but less shocking excuse. Nonetheless several of Cameron's close allies have told me the former is closer to what happened. Lansley was allowed to get on with it.

In such circumstances of unusual ministerial freedom, lobbyists' relations with members of the cabinet is obviously more of an issue. But even in this context most cabinet ministers are relatively weak, soon to be out of a job or in a new one. Cameron, George Osborne, their advisers and a few other ministers are key.

The main lesson of the Fox affair is not about lobbyists or the relationship between ministers and senior officials. Like most resignations, it casts light on the state of the governing party and, in this case, poses a key question. Beyond a more overt social liberalism, have the Conservatives changed enough since their defeat in 1997? If I were David Cameron, I would worry more about this question than lobbyists who inflate the importance of most ministers and ministerial relations with their officials, which in most cases is too respectful.

s.richards@independent.co.uk

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