Last weekend, a safe Labor state seat in WA was captured by the Greens, with Labor running second. That's not the first time this has happened. It has even happened at federal level, even if, as the calmer and more complacent Labor people will say, it is much more likely to happen at by-elections than at general elections, only ever happens in seats that are essentially strongly pro-Labor, and if the vote in question will almost certainly support Labor ahead of the coalition in tough votes in government. The Greens have been performing well for years, particularly in inner-suburban seats and in the more middle-class Labor seats, such as the ACT. So well indeed that a few Labor members, even high-profile ministers such as Lindsay Tanner and Anthony Albanese, must occasionally wonder whether about the arithmetic involved. Whenever the Greens run second to Labor in three-cornered contests, they must be favoured to win on Coalition preferences, since it suits the Liberals to have mavericks (even ones they dislike more) in power than Labor clones. When the Greens do well, but come number three, Labor can be fairly complacent, knowing they will get most of the preferences. Indeed, Labor can sometimes be safe if it comes in second so long as there are enough Green preferences to push it ahead of Number 1.

The size of the Green vote in some Labor constituencies, however, ought to be such as to have some Labor strategists worried. And for good reason. Complacent ideas that the Greens are but a left wing of Labor, that their preferences, if they are unsuccessful, will be overwhelmingly Labor, or even that the Greens have no real choice but to generally support Labor in power, deserve close examination. A good many old Labor stalwarts, including machine people, completely despise and dismiss the Greens and their constituencies. There's the use of phrases such as ''inner city elites'', and the continual charge that some of the social focuses of Green voters are based in living in some sort of la la land where people do not have to encounter ''real'' issues or the ''real'' problems of the economy.

They reflect a complete lack of comprehension of how and why issues such as an urgent need for drastic new policies on the environment, volubility about the rights of refugees, or Aborigines are vote changing issues for many people. Or how these appeal across the whole political spectrum.

''Old Labor'' claims to respect the drift of such impulses, but to regard them as secondary to bread and butter economic and industrial issues. It thinks that giving them too much attention can symbolise losing touch with the ''real'' voters. Some of them think that Paul Keating's late-premiership attention to such issues sealed his defeat. They view the interests of such constituencies at heart as middle-class issues and self-indulgences, compared with the hard realities of winning and sustaining power from the electorate. And, anyway, they think, those so motivated really have nowhere to go other than to supporting Labor, even on such issues, ahead of the Coalition. It might be nice to have now-Green voters voting direct for Labor, rather than a leftish alternative, but, so long as their preferences are safe, they are not a major problem. Their lack of concern is helped by convenience. A good many established Green voters perhaps 70 per cent are former members of the Labor Party, or tribal supporters, most of whom traditionally saw themselves as then being on the party's left. A good many of these left the party, or began a habit of withholding their No 1 vote as a protest against developing Labor pragmatism on what were seen as core Labor ideals. For many, the turning moment of Labor betrayal was over Tampa and refugee questions in 2001, but, long before that, many old Labor activists had become disillusioned by their incapacity to get Labor leaders, and Labor campaigners, mobilised over issues such as Aboriginal affairs, women's rights, multiculturalism, and defence of human rights. Not only did ''wedging'' by Howard make Labor wary and gun-shy about such issues; it also made it conservative and somewhat embarrassed.

Perhaps the Labor Left is doomed to permanent minority status, even within Labor. But historically, it has been the left which has been the engine room of Labor ideas and ideals. Just as importantly, it has been the left which has tended to make the party a beacon to the old-style activist convinced that participation and getting involved, and fighting the hard fight, is at the heart of creating change in politics. Even when they were romantic and impractical, the Labor left had a capacity to be the moral leaders of the party, and the ones who could appeal to hearts and emotions as well as to reason and the hip-pocket. By contrast, the right may have been more pragmatic and practical, perhaps the better at actually achieving that power which is a precondition for putting ideals into action. Perhaps the more adept in turning ideals into some sort of reality, however imperfect. But the right has hardly ever been a magnet for the idealist or the ideas person: its appeal, instead has been to the ambitious, even the careerist. Increasingly, in recent times, those careers have been marked out from childhood, with the backgrounds of Labor politicians, before election, being exclusively in paid employment in the party, in industrial Labor, or as minders in practical government.

The Left has not formally imploded, but has long ceased to be an academy of ideas, now instead being factionalised around personalities. There are a few leading left politicians, such as Julia Gillard, but it is increasingly difficult to see, from what they say or what they do, what it is that could define them as of a school of ideas different from the Labor mainstream. But the process has had two effects quite dangerous to Labor in the long term. First, those who control the party have increasingly lost faith in it as an organism capable of generating or sustaining ideals or ideals. Increasingly, instead, they treat ''Labor'' as a brand name like soap, and turn instead to advertising agents, public relations men and psychologists to feed them the cues to obtain popular support. Those involved in this process are particularly fearful of polarising issues, or ones which evoke visceral responses, since these are less predictable.

But second, and just as seriously, the energies, enthusiasms, and idealism of men and women particularly young men and women are instead being harnessed by groups such as the Greens. It is not a mere matter of transferring some sort of passive membership, or some capacity to be co-opted to hand out leaflets on election day. The Greens are recruiting activists, people who want to be involved, people who are getting involved because they care, and people whose ideas and idealism is taking them into a wider and wider vision of what government should be about.

Those who listen to Bob Brown, for example, will appreciate that while he still speaks regularly enough of core environmental issues, he is more and more addressing wider issues. To a substantial constituency of traditional Labor voters, he makes a good deal more sense than a Rudd government, forever seeming to be compromising to the point of ineptness on matters such as the environment, or seemingly unwilling to stand up for any sort of principle, for example on human rights. That Labor's fearfulness of gut issues inevitably takes it, because of Rudd's personality and instincts, to a morally conservative position. aggravates the disillusion.

If the polls are right, Rudd, and Labor is performing more than well enough that the electorate overwhelming prefers him, or it, to the Coalition alternative. Maintaining that position, and the general confidence of the electorate, takes work. But concentrating on it alone runs a serious risk that the real threat will come from behind: with more and more voters asking, in effect, is that the best you, and we, can do? Do your pathetic policies really show that we now treat climate change and greenhouse emissions seriously? Do you really think your response to some ''incursions'' by boat people represents a return to civilisation? Must we support you just because you are, or claim you are, less worse than the others? With younger people more predisposed to think this way than older voters, the sense that there might be something better can only grow.

Jack Waterford is Editor-at-Large.