A couple of months back, Scott Morrison won praise for convincing his climate-sceptic party to adopt a net-zero carbon target for 2050 - even though he had materially contributed to the problem for years.

The court drama surrounding Novak (no-vax) Djokovic is an even more acute example.

Despite the turgid legal argument, the full bench of the Federal Court had an extremely narrow jurisdiction which went not to the merits of the Immigration Minister's decision but rather to its validity as a legal instrument.

Inevitably, it upheld the ministerial discretion because that god-like catch-all was written into the act.

There had been two perfectly sensible options open to the government.

First, and most obviously was to refuse a visa application citing public health implications. This could have been signalled three or even six months ago - by way of clear public statement of national policy.

Who knows, it may even have led Djokovic to get the jab - after all, with 20 grand slam titles, he stood to become the most successful tennis player in history.

Nine of his 20 trophies come from Melbourne Park's Rod Laver Arena. This was far and away his best chance to reach 21.

The second option was to issue the visa. While riskier, this was in fact the course embarked on initially but should have carried with it onerous movement and masking restrictions.

Again, if those conditions were tight enough, the tennis ace may have concluded it was easier to get the jab.

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A third option, which no sane person would have chosen was to take options 1 and 2, reverse them, and then mash them together, making one unholy mess from which the only possible dismount was a spurious executive fiat and ultimately, the Federal Court tussle.

This was incompetence.

Despite a vast public service and bulging ministerial offices, the Morrison government plainly lacks political judgment and seems bereft of the most basic capacity to think forward.

This was evident with the vaccine procurement go-slow, the subsequent stroll-out, the related absence of a nationwide pro-vaccination campaign, and currently stuff-up of rapid testing kits as kids return to school.

None of these messes was unforeseeable. And neither was this eleventh-hour circus watched by the world.

It should never have come to this - a high-stakes last-minute debacle which has damaged Australia's reputation, sullied the Australian Open, and elevated a selfish privileged anti-vax athlete into some kind of martyr for a tawdry cause.

Still, the government got what it wanted in the end. Another high-profile case to focus pre-election minds on its "tough borders" stance.

The existence of such a diffuse ministerial power - to eject a non-citizen on the basis that their presence "might" cause social discord - is concerning. Laws are drafted carefully, and must contemplate the possibility of a minister acting on a political motivation rather than on a purely objective assessment of the national interest.

Now that this discretion has been exercised and upheld by a court, it is plain it would allow a conservative government to detain and then deport, say, Greta Thunberg because she had supported school strikes over climate negligence.

Is that what we want? This is still an open, free and determinedly liberal democracy, isn't it?