The shadows of Margaret Thatcher are legion, but beyond the scarring left by her policies it is now relevant to consider why she was popular with anyone at all. The answer is exactly the same reason she was unpopular: her conviction. This mysterious quality could again be the forebear of radical change in British politics.
The Thatcher revolution has been accepted by the four prime ministers who followed her, but none shared her power to remould society. A leader's ability to convince the public of the need for change was key for Thatcher and remains at the root of political possibilities as we stumble from one consensus-obsessed, risk-averse administration to another. Just as Thatcher persuaded enough people that self-interest was the route to a better society, any brave Labour leader must persuade enough people that a better society is the route to self-interest. To enact this requires the right circumstances and the right leadership. Britain's economic and social stagnation and the sense of rottenness at the heart of public life mean the first of those criteria is here. The second depends, barring something unforeseen, on Ed Miliband.
To challenge the status quo on the truly corrosive issues - public/private ownership and outsourcing, wage inequality, tax and financial regulation, transparency in public life - would require a level of conviction akin to that of Thatcher at the height of her power. Miliband must choose whether he wants to transform the country and its politics or settle for more tinkering as her latest successor. It would cause as much upheaval to address the wrongs of that legacy as it did to initiate them 30 or so years ago and releasing the tentacles of powerful vested interests would be a dangerous and arduous business. Upheaval is hardly one of Britain's recent strengths.
During the last time of great change none of Thatcher's achievements, however damaging and painful, could have been realised without an unusually strong conviction that what she wanted to do had to be done. This is what makes her such a different and difficult figure, though in a paradoxical sense, a model for Miliband. Just as in 1979, here is an opportunity to turn anxiety into an acceptance that radical change is needed. Whether that opportunity is taken may hinge on Miliband's ability to persuade the electorate that he is not just the latest alternative, but fundamentally different. It is at this point that conviction becomes decisive.
In the 1980s it was Thatcher's conviction that won her such loyal support and she persuaded sufficient numbers to join her in a radical and fractious change of course. The infamous housewife economics had a simplistic and intoxicating appeal and this myth is having something of a resurgence, though David Cameron and George Osborne are mere followers. They simply want to fulfil her project and their timidity has a stifling psychological effect as well as an economic one.
Tony Blair had the money and mandate to transform society, but despite some worthy investments, particularly in the NHS, New Labour was about gaining power first and governing second - a strategy all post-Thatcher governments have followed and been fundamentally weakened by. It's no wonder New Labour failed to live up to expectations. Nothing has done as much to damage the idea of politics as the agency for change in Britain as the wasted opportunities of the Blair years. This is what Miliband must not forget. For Blairites their leader was Labour's Thatcher, but unlike her, his beliefs and convictions remain a mystery. That is not a compliment to a prime minister who was in power for 10 years.
The success of Alex Salmond in Scotland is due in a significant part to his overt belief in something. Salmond can stand, and is thriving, on his difference to the rest of politics, however true this may be. His conviction is akin to Thatcher's in that it carries with it the potential for transformation. But even in the case of Scottish independence caution may turn out to be the nemesis of change.
Not only was Thatcher a divisive, destructive force in British history, but that is exactly what she wanted to be. That was the result of her conviction and we are still living with it. Her free market orthodoxy has barely been challenged and it would take a politician of unusual bravery to do so - and an uncharacteristically brave electorate to encourage them. But now may be one of those rare occasions when it is possible. That is not to say such circumstances could open the door for extremism; that is not the situation we face. However bad the recession and the resultant problems, the appetite is for a more equitable society and a balanced economy, not scapegoats and persecution.
Miliband's perceived weakness, that he is uninspiring and, dare it be whispered, "intellectual", could turn out to be his greatest asset when swing voters are faced with the prospect of more years of Conservative drift. His challenge then will be to persuade them that the status quo works against their interests - just as Thatcher did. But if he is to bring about substantial and lasting change it will only be achieved if he can make the link between prosperity and fairness, self-interest and public responsibility. He has already made one symbolic break with the past by ripping up her rolling contract with Rupert Murdoch. Perhaps Miliband will be the quiet radical some suspect him to be - William Rees-Mogg, of all people, has even made comparisons with Clement Attlee.
If he were to win office he would he require Thatcheresque zeal to combat the damage to social democracy accrued since her time in power and what fresh anxiety might that zeal, in turn, cause a generation who have accepted the Thatcher way as the norm? Fear of change keeps society stable but it also leaves it atrophied. This is our very British compromise and it is the history Miliband will be fighting against. The last time enough people demanded a political leader with conviction they got Margaret Thatcher. Change requires conviction, but conviction is a hazardous path into the unknown and it is one we are rarely willing to take. Miliband's job should be to convince us it is worth the risk.