WHEN any new set of circumstances arises, it creates confusion. If the rules that govern the situation are unknown, and must be deduced, constructed and applied on the hoof, mistakes, contradictions and reversals are inevitable.

Though it is the role of mainstream media to identify and examine them, and in the nature of social media wildly to exaggerate them, the public has been tolerant in accepting that uncertainty. While many basic things remained unknown, that was the correct response.

As the global progress of the disease continues, it has become clear that the correlation between outcomes, external factors – demographics, geography, climate and so on – and policy is not straightforward.

A few countries, such as New Zealand, which may have exceptional circumstantial advantages, have so far had great success. Others have done badly while adopting similar policies to their luckier neighbours. Over time, there often seems to have been a convergence of outcomes, even when the policies adopted were very different.

All the UK governments avowedly made their decisions on expert advice (their differences were trivial, and largely based on genuinely local circumstances). Since that advice often changed with the data, it is understandable that the rules changed, too. Diligently “following the science” is no guarantee of success when science is developing – think of the fact that the WHO was disparaging the use of masks only six months ago.

Now, however, more clarity and consistency is possible, and for practical purposes vital. The admirable aims of varying rules to ensuring NHS provision was best prepared and distributed, adapting to local requirements and trying to be flexible to preserve services and businesses may have been reasonable before.

But now, at a dangerous point in a second wave, with understandable public fatigue, and at a season when transmission is almost bound to increase, the plethora of national and regional tier structures has become an impediment, rather than a nimble response to prevailing local conditions.

It has led to absurdities in places like Hay-on-Wye, on the border of Herefordshire, moving down into England’s tier one, and Wales, all of which is aggressively going into lockdown. Northern Ireland’s need to do the same is declared urgent, but doesn’t come in until Boxing Day. Two-thirds of both Scotland and England are now in their respective high tiers, but the Christmas relaxations on travel and interaction remain.

Businesses across the UK, especially pub owners and restaurateurs, are in understandable dismay at the rapid changes; it was ridiculous that the furlough extension (welcome and sensible though it is) should have been announced after many employers had made plans on a different basis. Many schools in England, having made detailed provision for the post-Christmas period, are now having to revise them.

There has been one obvious, colossal achievement this year: developing vaccines in record time. Whatever mistakes the UK may be judged to have made when we are in a position to know (which may not be for a long time) it seems to have been successful here, creating, testing, approving, acquiring and administering an effective measure before anyone else in the West.

That is a testament to scientists, but also a firm ground on which policy can be clarified. When there is the prospect of significant ability to contain the disease, and of easing restrictions considerably, people may be willing – as they mostly have thus far – to accept that we still need to take the utmost care, but that an end (or a real improvement) is in sight.

That has little to do with whether you accept the need for continued constraints, think them too lax, or consider them excessive. The apparent view of all the UK governments that a forceful crackdown is required, but that Christmas should be different, may be politically understandable, but doesn’t make much sense. Chopping and changing rules, or applying them differently, no longer makes serves a purpose, even if it did once. At the moment no one is satisfied, because no one is clear.