There has been much to amuse in the Labor Right’s attack on the Greens over the last week, culminating in a flurry of attacks over the weekend: Paul Howes lambasting the Greens for advocating such pastimes as dancing over competitive sports for kids, thereby presumably at a stroke alienating the entire ballroom dancing competition community; John Robertson (remember him?) joining in, apparently forgetting the Greens were more diligent in supporting his head-in-the-sand stance on electricity privatisation than most of his own party; the febrile comparison by Sam Dastyari — general secretary of that politically deft outfit, NSW Labor — to One Nation.

The participation of union leaders like Howes and Tony Maher, who joined in on Twitter, was intriguing, given the Greens are far more protectionist than the parliamentary wing of Howes and Maher. In April, for example, the Greens not merely supported the government handing out yet more wasteful assistance to the automotive industry, but wanted to explore ways to prevent a future Coalition government from removing it. For a leader like Howes, who prides himself on advocating measures to protect jobs, having a crack at the Greens looked a little perverse.

Howes complained of the Greens “cannibalising the progressive vote”. Putting aside that under preferential voting, cannibalising votes is very tricky to achieve, it’s worth taking a proper look at how realistic the Labor Right is being in demonising the Greens.

The problem with the thesis that Greens voters are just Labor left-wingers lured to the Greens by the Siren-like singing of Kumbaya is that it has at best only been true for the last couple of years. The state-by-state picture varies, but the rise of the Greens from a nonentity party garnering 2-3% of the Senate vote in 1998 to the balance of power party now was primarily because of the decline of the Democrats. In state after state, Senate votes show that the self-immolation of the Democrats was accompanied by the rise of the Greens: whether disgruntled Democrats voters shifted directly to the Greens or not, the Greens have replaced the Democrats as the home for third-party voters.

In South Australia, the Democrats stayed higher for longer, because of the party’s historical strength there and, likely, the popularity of Natasha Stott-Despoja. That kept the Greens vote lower there for longer. In Tasmania, where the Greens have been much stronger for longer, the Democrats had already declined by the late 1990s, but Brian Harradine attracted a stronger third-party vote than the Greens. It was only his absence from the ballot in 2001 that saw the Greens vote surge into double figures. Elsewhere, the decline of the Democrats in the Senate vote mirrors the rise of the Greens.

Same in the House of Representatives in NSW. In 2001, the Greens were only slightly ahead of the Democrats across NSW, but both were below 5%. In 2004, the Greens nearly doubled to 8% and the Democrats practically vanished. In Anthony Albanese’s seat of Grayndler, the Greens shot to over 20% of the vote in 2001, increasing their vote by about the same margin as the Democrat vote fell. Ditto in Tanya Plibersek’s seat of Sydney. In Victoria in the House, the Democrats were slightly ahead of the Greens in 2001 but were on around 6% of the vote each. The Democrats have since becomes asterisks while the Greens vote has doubled.

The electoral establishment of the Greens was built on the wreckage of the Democrats, not by siphoning off left-wing voters from Labor.

That only really applies to 2010, when the Greens rose to levels of support beyond those achieved by the Democrats. In NSW, Victoria, Queensland and Western Australia, the 2007 election saw the Greens basically matching, or only slightly bettering, the levels of support achieved by the Democrats in 1998 in the Senate. But in 2010 they burst through into double figures, even in South Australia.

According to Essential Research, which consistently gives a lower voting intention to the Greens than Newspoll, the Greens have sat on 10-11% since the 2010 election, unaffected by the carbon price, asylum seekers or Bob Brown’s departure. If maintained, it’s the electoral basis for an ongoing presence in the Senate of 10-12 senators. If for nothing else, Labor will have to get used to dealing with the Greens in the Senate, regardless of who’s in government.

What halts the Greens are strong swings against governments. The Greens’ federal vote went backwards in NSW in 2007 in the House of Representatives. It only rose by 0.7 percentage points in Victoria. The NSW and Queensland state elections show that the Greens struggle when the electorate is gunning for the incumbent. To amend the cliché, when the swing’s on, it’s on against minor parties. On that score, maybe the Labor Right will achieve its goal of halting the Greens momentum at the next election by handing Tony Abbott a landslide.

That of course points to Labor’s real problem: if there’s been any “cannibalising” of the progressive vote by the Greens, it’s now been replaced by a massive shift of Labor’s vote to the Coalition. The Labor Right may lament Labor voters who’ve shifted to the Greens, but even if Labor won all of them back, plus all of the third-party voters who moved to the Greens with the demise of the Democrats, it won’t save the party from annihilation; it’s the much larger number of former Labor voters who are now parked firmly with the Liberals that are the problem.

And Labor, as Sarah Hanson-Young pointed out in a succinct summary of the problem yesterday, is the odd one out of the major parties and the Greens. There is no lack of clarity about what either the Greens or the Liberals stand for, and little gap between the parties’ bases and the parliamentary parties’ policies (this is one of the reasons why neither is moving on asylum seekers). But there is little clarity about what Labor stands for. There’s plenty of talk about “fairness” and “working Australians” but no visceral feel about what the party’s core values are, the sort of values that mean voters don’t even have to think when they wonder about what a party stands for.

Lecturing both third-party voters and disaffected former Labor supporters about how stupid they’re being supporting the Greens probably isn’t the smartest way to attract their votes. But doing it when they don’t have a clear idea what Labor values are guarantees failure.