They cleared the front-page of the Standard on Monday after the elder Miliband repeated the proposal in an interview, followed up by the press association, the Daily Mail, the Mirror and others.
The leader writers didn't approve either:
The policy would hit more than 34,000 people in London and 80,000 in the country as a whole.
Yes - out of 14 million home-owners in the UK, as the Standard did not mention, in its challenge to a "policy which would hit London hard" - albeit without affecting 7.9 million Londoners.
The average property price in the UK is £167,425, according to the Halifax.
The Standard is currently running an excellent and imaginative Dispossessed campaign to highlight inequality and social exclusion in London. Miliband says the mansion tax would mean the government could afford not to impose blanket housing benefit cuts of 10% on long-term unemployed, which could see many families have to leave their homes.
Should more than 34,000 Londonders be affected by the government's housing benefit changes, we can surely expect an imminent front-page splash to highlight that too.
Left Foot Forwardpoints out that Vince Cable's earlier proposal mansion tax on houses over £1 million was backed by 57% of voters, with 27% against, with Conservative voters also in favour. This polling evidence was not deployed as effectively as it might have been by Vince Cable and the LibDems when under fire for the policy, though Cable did argue the fairness case for the policy.
It is frequently the case that political parties are accused of "abandoning the centre-ground" by newspaper commentators for making proposals which have 50-70% public support - as was also the case with the 50p tax rate on earnings over £150,000.
One rather hypothetical sociological explanation might be that such proposals impact a higher proportion of newspaper editors and commentators, and their immediate social circle, than that of their readership.
The Standard did quote at length Trevor Abrahamson of Glentree Estates, who offered a detailed economic model explaining how the property tax could could put off wealthy foreigners, destroy consumer confidence and so bring down the entire British economy: "“Anyone with an ounce of nous wouldn't even suggest this policy, let alone implement it ... The British economy is far too dependent on the property sector to do something like this.”
David Miliband has been pitching the idea for the last couple of months, including it in a Guardian article six weeks ago, though the paper placed more emphasis at the time on his proposals to restrict charitable relief for private schools.
Miliband has since included it in his mid-July leaflet to 200,000 party members, talked about the policy at hustings debates, talked to the New Statesman about the policy. Next Left felt it was indicative of his centre-left pitch for the leadership.
So I hope he is pleased to have some greater media attention paid to the policy and will take on the challenges to it.
At LibDemVoice, Stephen Tall points out that the mansion tax remains LibDem party policy too, making it a happy point of policy convergence among some (but not all) of the political parties which like to call themselves progressive.