Politics, like much of life, is replete with mythology. A current myth, much embraced by journalists, is that Julia Gillard is prime minister today due to support from the Greens.

For example, when interviewing the Labor MP Joel Fitzgibbon on the ABC”s RN Breakfast yesterday, Fran Kelly asserted that “Labor is in government because of the Greens”.

Not so. Labor won 72 seats in the 2010 election, well short of the required majority of 76. When Adam Bandt, the Greens MP for Melbourne, declared his support for Gillard she was still short of the required numbers.

Labor is in government primarily because of the support of two rural independent MPs, Rob Oakeshott and Tony Windsor. Gillard has received praise for negotiating an agreement with the Greens, which she and Wayne Swan signed on September 1, 2010. However, no deal was necessary. On August 15, 2010, soon before the election, Bandt was reported in The Age as saying that he would support Labor in the event of a hung parliament.

In the past couple of days there has been a virtual explosion of anger from sections of the Labor Party towards the Greens. On Saturday, The Weekend Australian revealed that the NSW Labor”s general secretary, Sam Dastyari, had compared the Greens with One Nation. The following day, writing in The Sunday Telegraph, the Australian Workers” Union”s national secretary, Paul Howes, accused the Greens of having a “grab-bag of loopy and out-there policies”.

Dastyari restated his views on Sky News”s Australian Agenda program on Sunday. Then, Fitzgibbon, the chief government whip, bagged the Greens” policies as either “populist and unachievable” or “achievable and economically destructive”.

This line of attack was soon taken up in Melbourne. The leader of the Labor Opposition in Victoria, Daniel Andrews, wrote an opinion piece in The Age yesterday, in which he depicted the Greens as “idealistic outsiders”.

So, why the attack? And why now? First, there is the question of timing. The NSW ALP conference is on in Sydney this weekend. And in a couple of weeks” time there will be a byelection in the once-safe Labor state seat of Melbourne. The contest is between Labor”s Jennifer Kanis (a lawyer) and the Greens” Cathy Oke (an environmental education consultant). Both candidates are Melbourne City councillors.

Then there is the question of policy. All the opinion polls say Labor is facing a wipe-out at the next election. The two issues hurting the ALP are the carbon tax and border protection. Item six of the Labor-Greens agreement of September 2010 requires the introduction of “a price on carbon”. This led to Gillard”s announcement in February last year that there would be a carbon tax, under the government she led.

Gillard”s breaking of her commitment not to introduce a carbon tax is particularly hurting Labor in the outer suburbs and regional centres. There, voters on modest incomes face rapidly increasing power bills in a climate of job insecurity.

Then there is the issue of asylum seekers. Again, concern that Labor has lost control of Australia”s borders is greatest outside the inner-city areas. Here the policy of the Greens” leader, Christine Milne, and her colleagues not to reach a compromise with Gillard makes it possible for the likes of Dastyari to make a pitch to Labor”s traditional lower socio-economic base in the suburbs and regional centres, many of whom are immigrants.

In other words, the times suit the attempt by some ALP operatives, based on the NSW Labor Right, to win back primary votes.

But this is only part of the story. There is a considerable ideological divide between a century old party which has its base in the old-fashioned working class and an environmentalist movement whose support is based on voters in relatively secure employment in the public sector, or in white-collar industries.

In short, many Labor MPs and trade union officials believe that the Greens do not care about job losses in what they regard as environmentally unfriendly industries. And they have a point. For example, writing for newmatilda.com on May 28, the NSW Greens Senator, Lee Rhiannon, and a freelance writer, Paul Fitzgerald, called for the scrapping of Sydney Airport and for a replacement to be built outside the Sydney Basin. Such a policy, if implemented, would destroy thousands of jobs and devastate the Australian economy.

Then there is history. In 1968, the Communist Party of Australia (CPA), under the leadership of Laurie Aarons, broke ties with the Soviet Union. In time, the CPA was wound up. In Victoria, the old anti-Moscow CPA collapsed into the Socialist Forum, which became part of the ALP.

In NSW, however, the CPA withered on the vine. But not all Communist Party members in NSW split with Moscow. The pro-Moscow communists formed the Socialist Party of Australia. Rhiannon joined the SPA in about 1970 and remained connected to the pro-Moscow communists until 1990, the time of the collapse of European communism.

These days Rhiannon refuses to answer questions about her activities in Eastern Europe in the 1970s and 1980s and, in particular, whether she attended the International Lenin School in Moscow in 1977. But it is little wonder she and some of her colleagues annoy such Labor MPs as Michael Danby, Eric Roozendaal and others on the Labor Right, including Howes. They regard the Greens not as an environmental movement but, rather, as a leftist organisation that is opposed to social democracy.

Rhiannon”s hostility towards Israel is another bone of contention, since Labor has supported Israel from the time when Ben Chifley was prime minister.

Some Labor supporters have always opposed the 2010 ALP-Greens agreement. That”s no myth. They are beginning to speak out now.

Gerard Henderson is executive director of The Sydney Institute.