As the latest round of social directives sinks in and Australians tussle with the (in most cases rhetorical) question of why they can only invite three people to their wedding but nine to their squat challenge in the park, the better question to ask is a broader one.

Why does public advice seem to disagree with itself? Why are federal and state governments saying different things?

The messages are confusing. But the reasons for the differences are pretty simple.

In politics, it's always important to remember who's talking, and what skin they have in the game. What are their responsibilities and their risks?

In last night's National Cabinet meeting, as has been happening for some time now, the Victorian Premier pushed for a full lockdown like Britain's. This is an approach that is resisted by the Federal Government.

Here's why. State governments run hospitals. State health ministers and premiers are the political figures with the most scar tissue from hospital disasters. So anything a state leader can do to "flatten the curve" is not only in the interest of public health, it's also in the interest of their own personal political health.

What about schools?

State leaders are also much less likely to achieve social distancing from teachers' unions; it's why they are much more sympathetic to the idea of closing schools. Oh yeah — they run schools, too. They want to reduce numbers of kids at school to safeguard teachers, which is why NSW and Victoria have gone further than the Federal Government on this front.

Why is the Prime Minister continuing to advise that schools should stay open?

First, because the Chief Medical Officer is advising him that there is not compelling evidence that kids get infected with this virus. Second, because sending kids to school makes parents more able to do their day jobs.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 1 minute 22 seconds 1 m 22 s Victorian Premier Daniel Andrews said people should stay home if possible.

And Centrelink?

Which brings us neatly to the third point: While hospitals are the states' responsibility, Centrelink is the Commonwealth's.

The welfare of the economy more broadly is a Commonwealth concern.

Which is why the PM is parsing all these announcements as finely as he can.

It creates confusion, but the PM's objective is to keep every single person in work who can feasibly be kept in work. Every person who stays in work is one fewer person lining up outside a Centrelink office.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 42 seconds 42 s Queues form outside Centrelink offices for the second day.

The wedding problem

Let's go to the wedding/boot camp comparison (first taking a moment silently to reflect that we have now lived long enough to see an Australian Prime Minister, late at night, getting deep into the weeds on why a marriage is different from boot camp, as well as mentioning "waxing" to an upsettingly unprecedented degree).

Why do weddings have different rules from personal training sessions?

Well, a wedding is indoors, under the PM's broad presumption (this is not always the case, of course). The celebrant (one of the five permitted participants) is getting paid. They get paid the same whomever is there. The social purpose of the wedding (two people being joined for life so they can go home and quickly go off each other on Day One of working from home together) is fulfilled no matter how many guests are there.

"Now, what we're talking about of people up to 10 for a training, that is a business, that is someone's livelihood," explained the Prime Minister last night.

"And you're saying that I should turn their livelihood off and I'm not going to do that lightly. And if it's not believed to be necessary based on the medical expert advice, I'm not going to be cavalier about people's jobs and their businesses."

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 1 minute 23 seconds 1 m 23 s Mr Morrison said private gatherings in homes should be kept to "very small numbers of guests".

Two images shows the conflict

It seemed odd, in the middle of the nation's greatest crisis in living memory, to hear our leader discussing "boot camps" in such detail. (Earlier, Mr Morrison had tried to pronounce the word "barre" and failed, leaving an anxious nation gripped temporarily by fear that French headwear was also to be denied us for the immediate future.)

But as an example, it's a pretty good illustration of the conflicting interests the PM is trying to juggle here. Is he making the right call? We are a democracy. The nation will cast its judgment in due course.

"Understand this," the PM continued. "This country is not dealing with one crisis. We're dealing with two crises. We're dealing with a health crisis that has caused an economic crisis.

"And I am very concerned about the economic crisis that could also take a great toll on people's lives, not just their livelihoods, the stresses that that will put on families. The things that can happen when families are under stress. I'm as concerned about those outcomes as I am about the health outcomes of managing the outbreak of the coronavirus.

"And it is a delicate task for the National Cabinet to balance those two. Lives are at risk in both cases. And so the National Cabinet won't just rush on the sense of an opinion of inevitability. We will calmly consider the medical advice that is put to us and weigh those things up and make sensible decisions as leaders. I will not be cavalier about it, and neither will other premiers and chief ministers."

If you want two images that express the extremes of the potential disasters that face our nation right now, one is every Australian queued up at Centrelink and the other is every Australian gasping in a hospital corridor.

That's the reason for the differing advice; different leaders are placing themselves at different points along that continuum, depending on what it is for which they're each responsible, and depending also — as usual — on what they value most, which varies according to ideology.

Two movements are emerging

The "Save the economy, and let the health consequences rip" argument doesn't seem to have much mainstream traction here. It's bigger in the United States, where Donald Trump has repeatedly mused that he would like to see social distancing ease off soon, and Texan senator Dan Patrick called on seniors to sacrifice themselves for the economy.

The "Shut everything down, and hang the economy" movement is more established in Australia. And it's true that if everyone in Australia retired to a 2x2m space and had no contact with anyone for a fortnight, the virus would be stopped in its tracks.

But a lot of people would die that way too.

In the absence of either pure approach, we have what we usually have in the world of democracy: An imperfect and messy compromise, in which we are asked to trust our elected representatives to make the right call.

The fact that trust in our political system is at an abysmal low right now is an almost cartoonishly cruel coefficient, given that for any Government directives to work as intended, they need to be complied with widely.

In these circumstances, responsibility for one's own behaviour becomes hugely important. As does awareness of others' circumstances.

Not everyone has the capacity to stay home. Not everyone can afford to shut down. And our essential workers (in health, education, transport, logistics, food supply) are in some cases being asked to take on monumental burdens and risks, for which the rest of us should be devoutly grateful.

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