At the time of the February cabinet reshuffle, eight weeks and an eternity ago, I was talking to a senior Tory about the power structure of the government. He remarked: “Boris is not primus inter pares. He is first without equals. He is president, he is lord of all he surveys. The cabinet are just nodding dogs.” As if to illustrate this, President Johnson let TV cameras into the cabinet room to film his ministers performing a ridiculous nursery school call and response about their manifesto promises.

The “lord of all he surveys” is now confined to hospital by the coronavirus and the “nodding dogs” must do their best to prove that they do not deserve that derogatory label. A structure designed to concentrate the maximum amount of power at Number 10 must adapt to operating without a fully functional prime minister.

His enforced absence coincides with an especially testing stretch of the crisis. What is crudely characterised as the “lives versus livelihoods” argument is becoming sharper. There is a mounting debate within government about when and to what extent the lockdown might be relaxed. This is, paradoxically, a testament to its general success. Thus far, it has worked more effectively than government modelling anticipated when the prime minister reluctantly placed a closed-for-business sign over most of Britain. Some doltish police officers have overstepped, a giant dunce’s cap being awarded to the chief constable of Northamptonshire for threatening that his coppers would check shopping trolleys for “non-essential” items. A recalcitrant minority of the public are behaving stupidly. But these are the exceptions, not the rule. There is both extensive compliance with and wide support for the lockdown.

The initial anxiety within Number 10 that the citizenry would rapidly become rebellious has not been justified. I detect a tentative confidence among ministers and their scientific advisers that the lockdown is having the desired effect of preventing the outcome that petrified them most. The fear three weeks ago was that the NHS would be engulfed by many more cases than it could possibly handle, leading to huge numbers of avoidable deaths. Public horror would have been swiftly followed by public disgust with the leaders who allowed such a catastrophe to happen, irreparably shattering the Johnson government’s authority and credibility. One senior Tory remarked to me at the end of last week: “I take a big gulp before I say this because I know I am tempting fate, but the fact that the London Nightingale is not full at the moment is grounds for optimism.”

The other side of the coin is the terrible cost being inflicted on businesses and jobs by imposing a hard stop on the economy. Ministers knew it would be dreadful, but didn’t anticipate just how atrocious. The Treasury is now expecting a whopping 9m applications for the job retention scheme that subsidises the wages of furloughed employees, three times the number budgeted for when Rishi Sunak launched his emergency measures. So we have indications that the most diabolical scenarios for deaths may be avoided while the economic penalties are becoming increasingly stark and that combination is reshaping the politics of the crisis. There are rising demands from the headline-hungry media, an attention-seeking opposition and stricken businesses for the government to start outlining an exit strategy.

Ministers are hugely reluctant to do this for two main reasons. One is their anxiety that any talk about an exit from lockdown will dilute the “stay at home, protect the NHS, save lives” messaging. The other reason ministers don’t want to talk about an exit strategy is that they don’t have an agreed one. As a figure at the heart of decision-making puts it: “There is no get-out-of-jail-free card from this crisis.”

The most assured way back to normality is mass vaccination, but it is generally thought that a vaccine is a year to 18 months away. The assumption in government is that you can’t keep a modern economy in an induced coma for that long and expect to have many businesses and jobs still breathing by the end of it. Absent a vaccine, all sorts of notions for a phased easing of the lockdown are floating around Whitehall. Many of them shrivel under scrutiny. One suggestion is a partial relaxation based on age, so that twentysomethings could return to work. There would be problems with policing that successfully: “You don’t look younger than 30 to me, sir. Show me some ID.” And most enterprises do not depend on just one age group. Another notion floated is that the severity of the lockdown might be varied from region to region. There are some difficulties with that. If the pubs were reopened in London, but remained shut in Manchester, how would Mancunians react to TV footage of Londoners flocking back to their boozers? “The worst of all worlds,” says the city’s mayor, Andy Burnham. “That’s when you get a riot,” remarks a former Tory cabinet minister.

The great hope among the politicians is that science will rescue them from the “lives versus livelihoods” dilemma. There was a period when the government became excited about the idea that we could find out who has had the disease by using antibody tests. That was hailed as “a game-changer” by Mr Johnson before he was incapacitated. Millions of kits were ordered from China only for them to be found unreliable. There is a decent chance of eventually securing an accurate antibody test. It would be valuable to be able to tell NHS staff and other key employees that they had immunity and were safe to work. But it doesn’t solve the problem with the general population. The latest guesstimate from the government’s scientific advisers is that no more than 10% of us have had the virus. Even if you could identify them, this leaves 90% exposed to the risk of infection. That is not a route out of lockdown.

When the histories of this crisis are written, it is likely that they will conclude that the colossal misjudgment initially made in Europe and America was to think this threat was similar to that from pandemic flu. Asian countries, battle-readied by earlier encounters with coronaviruses, treated the menace like Sars and Mers. South Korea has never had more than eight deaths on any one day and has achieved this feat without a national lockdown.

That is generally attributed to their comprehensive programme of community testing and contact tracing. A similar strategy may become feasible for Britain if the government can make good on Matt Hancock’s bravura promise to get up to 100,000 tests a day. But it is no panacea. The South Korean formula requires the redeployment of vast numbers of local and central government officials and wouldn’t work without near universal public trust and co-operation.

Many in the cabinet are aghast at the crushing of the economy and the prospect of a contraction sharper than anything since the 1930s. They will seize on any apparently better news to argue for the earliest possible relief from lockdown. This faction is not being very noisy while bulletins report around a thousand UK fatalities a day. It will be when the casualty rate is on a downward trend that the put-the-economy-first lobby will start to apply serious pressure. Others in government are worried that passing the peak will be the most perilous phase of the crisis because it will be accompanied by a clamour for an end to restrictions. One senior adviser warns: “To suddenly switch from ‘we’ve got it under control’ to ‘release all measures’ would be a terrible mistake.”

This won’t be like the end of prohibition in America. There won’t be an overnight flip from suppression to freedom to live life to the full again. What we will likely see is experimental relaxations of some restrictions. If the government gets it wrong, there will be a risk of a second wave of infections that forces them to reimpose a lockdown.

When this crisis broke, I suggested that ministers would be faced with hideously difficult tradeoffs between curbing the menace to life posed by the disease and the damage wreaked by widespread bankruptcies, mass unemployment and the implications for Britain’s future ability to finance public services, all of which will have effects on mortality.

This is the sort of decision-making that prime ministers are elected to lead. When members of the cabinet wish a speedy recovery for Boris Johnson, it is not just because they want to express sympathy with a poorly boss. It is because they know that the toughest choices of this crisis have yet to be made.

• Andrew Rawnsley is Chief Political Commentator of the Observer