In this context, keeping the border between NSW and Victoria open was an important symbol of that unified cross-state effort.
And it had limited practical consequences. Other than for those in Albury-Wodonga, where a hard border closure would have meant cutting off 35,000 or so Wodonga residents from access to the nearest hospital, it did little to encourage actual movement across state lines.
At the time, no one in either NSW or Victoria was allowed to leave their homes except to perform essential work, to exercise, go the doctor, or to the supermarket. There was certainly very little likelihood that they would be going hundreds of kilometres away on holiday, or for a work trip to another state, without facing substantial fines and community disapproval.
We now confront a very different landscape. Cross-border cooperation and a truly national effort to combat the virus has been achieved. People are mostly free to leave their homes and to engage in travel for leisure and work purposes.
And Victoria and NSW are facing very different public-health challenges. Victoria is grappling with a new peak in COVID infections that requires a return to strong and tough measures, at least in certain areas.
NSW, in contrast, has elimination – not just containment – of the virus within sight.
This is also the ultimate prize in the fight against COVID – a prize valued by public health experts and economists alike.
Containment means that the chances of contracting the virus are substantially reduced. It means that those who contract the virus can count on a hospital bed being available. And it therefore means that the chances that vulnerable members of the community will die from the virus are significantly decreased.
But it still means continued social distancing, sporadic work and school closures – and voluntary self-isolation for many older Australians and vulnerable members of the community.
And it means continued economic uncertainty and weak consumer and business confidence.
Elimination, by contrast, could allow everyone in our community to return to their normal routine with confidence – and to reap both the social and economic benefits that come with that confidence.
Australia without international travel will be a very different place, and one that sees lower economic growth than an open Australia. But unless and until a vaccine is developed and widely deployed – something that is perhaps years not months away – the best chances of a return to economic prosperity lie in eliminating the virus within Australia.
And that is what NSW is close to achieving.
Therefore, we cannot risk going back to a fight for containment – or the kind of fight that our Victorian friends and allies are regrettably confronting. And relying on the good will of citizens not to travel does just that. It does not do enough to prevent the risk of a second peak in NSW.
To avoid the risk, NSW needs urgently to close its border with Victoria.
An intervention of this kind is not just good for public health – but also working parents, few of whom want to go back to working from home with our children being home-schooled.
Closing the border should be a temporary measure and constantly revisited. And it should be designed to allow those in Albury-Wodonga to be exempted for localised travel across the border. This would create a kind of Albury-Wodonga “green zone” that would prevent the otherwise significant disruption to that community, and be practically very difficult to enforce.
But it should be an urgent priority for the NSW government that so far has got almost everything other than cruise ships right. Times have changed since March, and it is time for the government to change with them.
Rosalind Dixon is a professor of Law and Director of the Gilbert + Tobin Centre of Public law, and Richard Holden is a professor of Economics, at UNSW Sydney.
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