When challenged on immigration yesterday, Julia Gillard ducked for cover. Unwilling to even admit the logical consequence of her concerns about sustainable population, that she would have to reduce immigration, she offered a distraction about “issues about water about soil about city planning about infrastructure and services.”

There’s a powerful constituency for high immigration in this country. Business strongly supports it. So too do a number of mostly conservative media commentators, and some libertarians. And for generations, both sides of politics have backed high immigration as well.

But throughout that time, despite the benefits of high immigration being manifest, they have failed to carry the case with the wider electorate, and convince ordinary Australians — most of whom, of course, either come from overseas themselves or who are descendants of immigrants — that maintaining high immigration is important.

State Governments in Queensland, NSW and Victoria, which have systemically failed to invest in infrastructure, and which have laid obstacle after obstacle in the way of a market response to housing demand, have also failed.

Now, if their rhetoric is to be believed, a new generation of political leadership is turning its back on high immigration with the aim of securing the support of voters disillusioned with long commutes, poor public transport and their inability to afford housing except on the fringes of our cities.

This is a colossal failure of policy, management and political communication, and it will have significant consequences for generations to come.