To some extent it is easy to comment with the benefit of hindsight. That said, the government – and this includes many highly-paid officials – have spent tax-payers money on anticipating and planning for health epidemics. And so they should at least have had a viable plan in a drawer somewhere. And sufficient stores of the necessary equipment and ability to carry out tests.
It is interesting to note a report in the Daily Telegraph  that the computer code for the Imperial College modelling which has informed the lockdown decision is being described by software engineers as a “buggy mess”. This writer is also a software developer and I am not in the least surprised to learn that code written by non software expert academics is a mess.  More to the point; the models (which contributed to the original lockdown decision in the UK) appear ridiculously unreal: “The Imperial model works by using code to simulate transport links, population size, social networks and healthcare provisions to predict how coronavirus would spread”. As an IT expert I can say that this sounds like an impossible task; too many unknowns and too many assumptions. “Buggy mess” or not I would not expect anything credible from this, which sounds like a classic example of academics amusing themselves (at public expense) and not producing anything which could possibly have any serious bearing on the real world.
It is a sign of the times that the government says it is “following the science” (itself a smokescreen designed to evade responsibility) and the “science” itself turns out to be a combination of questionable population modelling and behavioural ideology.
The main facts about Sars-Cov-2 and Covid-19 are known. They were in fact evident at least on a provisional basis by early March (in fact much before). At this point it was known that Covid-19 is a serious clinical disease. It was known that it spreads quickly and asymptomatically. It was also known that it is very serious for people over the age of 50 and/or those who have existing health conditions, but that for healthy people under the age of 45 there is a low mortality rate, possibly comparable to flu.
The UK government appears by any measure to have bungled this to an extraordinary degree. They have taken steps which will knock a swathe of GDP. They have created a debt mountain that will take a long period of time to pay off. The economic effects will be medium-term. At the same time they have succeeded in allowing 50,000 (an estimate; you cannot rely on the official figures which currently stand at about 35,000) people to die. The vast majority of these deaths were avoidable. In South Korea (with a population of 55 million) there have been around 260 deaths. This cannot be explained away either by a question of statistics or by some posited genetic protection which South Koreans enjoy. The most likely explanation is that the South Koreans implemented a rigorous track and trace programme as per WHO guidance. There was a more limited lockdown in South Korea which relied heavily on voluntary social distancing. 
A cool and objective strategy for Sars-Cov-2 would have included the following:
- Take it seriously. The UK government behaved in a flippant and hard to understand way in March. Even as the scale of the disaster in Italy was unfolding in front of us the UK government did nothing. People were allowed to fly in from Italy, including thousands for a football match on 11 March, and tens of thousands were allowed to fly back from their holidays with no quarantine or even health checks at the airports. It really was as if the government believed that some kind British superiority would protect us. It didn’t. (Or; were they deliberately trying to create mass infection and so get the fabled ‘herd immunity’? If that was so it is criminally negligent that they didn’t take the next step).
- Recognizing that the elderly and those with existing medical conditions were at risk. From early March – when this was 100% evident based on the Italian experience – completely locking down UK care homes. This simple step would have saved the lives of at least 10,000 people who had every right to enjoy the remaining months or years of their lives. This measure still hasn’t been taken and more people continue to die completely needlessly as a result. When Ministers talk about the “tragic” deaths they are feigning care. You can’t care about a death you could easily have prevented but have chosen not to.
- Taken steps to acquire sufficient testing capacity and Personal Protective Equipment (PPE) in advance. Public Health officials are paid to plan for contingencies. It is clear that they didn’t – despite wasting public money on simulation exercises. The results (or lack of them) of this prior planning were then exacerbated by ideologically driven failures to join in an EU procurement scheme and, it seems, a series of bungled and panic-driven commercial cock-ups – purchasing PPE and antibody tests which on delivery turned out not to work. It was too late to do anything about the failures to plan in advance but there doesn’t seem to be any excuse for the failure to get to grips with the resources situation in February and early March.
- Take a realistic and clinical approach to lockdown and quarantine – based on reality not on academic modelling. This should certainly have included asking the elderly and at risk to stay at home much earlier than they were asked. (After 22 March and 7 weeks after the WHO declared a health emergency of international concern). The extent of the necessary lockdown is of course arguable. But if the at-risk groups had really been protected – and they were not and are not being – and if measures such as quarantining arrivals and tracking cases had been implemented early then the scale of the lockdown could have been less.
Everything seems to have been done as a panicky and ill-thought series of steps – a series of stable doors being bolted one after the other after each horse has left its particular stall. The government attempts to justify its decisions by saying they are based on “the science” – but it appears they may have been listening not to clinicians and hospitals but to “behavioural scientists” (not, in fact, scientists at all but ideologues) and modellers  – whose contribution may have wildly mislead them. It may be that the cozy group of “scientists” advising the government suffered from a kind of group think. This view is argued here. It appears, possibly, that obsessing over the models and and “behavioural science” they may have simply missed the obvious practical steps; quarantine arrivals, lockdown care homes, test and isolate etc.
In short the UK’s response seems to have been a huge disaster. It takes some doing but somehow the UK government appears to have achieved the worst outcome they possibly could; high mortality and high economic damage.