The Government has introduced what it calls “Plan B”, including face masks in non-hospitality indoor settings, working-from-home guidance and vaccine passports for large events. It’s scientific advisors have declared we should reduce social contacts. Boris, on the other hand, says everyone’s Christmas parties and nativity plays should proceed. Cue many gags about how last year one had to pretend to be at work to go to a Christmas party, but this year one has to pretend to be at a Christmas party to go to work.

Why is it doing this? Well, that’s not terribly explicit. The argument appears to be “Something, something, protect our NHS.” At current growth rates, Javid tells us, omicron is scheduled to reach one million cases per day by the end of this month. And with Plan B, the date at which we reach one million cases a day would be what? January 2? Omicron cases are currently doubling every two to two and a half days. Wearing a face mask in the cinema but not the pub isn’t going to make a lot of difference to that.

If omicron is really going to grow as explosively as the Government suggests, Plan B isn’t going to come remotely close to slowing it down or stopping it. Restricting people’s lives in a way that makes no difference whatever to a problem is just as authoritarian as restricting people’s lives when there is no problem at all. If the only point of restrictions is as a kind of virtual flag with “We’re doing something” written on it, it’d be better not to restrict people’s lives but instead to raise a literal physical flag saying that, outside 10 Downing Street.

Maybe, then, the Government should be imposing much more restrictions – a full lockdown, say? But restrictions to prevent precisely what? As matters stand, it appears plausible that omicron will very rapidly (much more rapidly than anything we’ve seen up to now) infect almost everyone whose only current source of immunity is a past infection with one of the earlier variants (unless that was very recent), plus a large portion of those that have only been double-vaccinated so far. But the current studies suggest that those that have been triple-dosed or that have had at least two doses and a past infection (so-called “hybrid” immunity) are likely to stay immune to omicron.

Well, in the UK we’ve triple-dosed 37 per cent of over-12s and there are probably around another 15-20 per cent of us that have had two doses and a past infection. And those groups include all the people most vulnerable to dying or being hospitalised. So it would be perfectly possible to have a very large omicron wave with relatively few hospitalisations. And an omicron wave might burn very rapidly through those it could infect but then die away almost as quickly as it appeared, leaving the well-protected largely untouched.

The Government wants to say imposing restrictions is legitimate just in case hospitalisations ended up being very high (and just in case Plan B made any difference to that). But “just in case” is not a legitimate basis for restricting people’s lives. There needs to be a high likelihood that some disaster will follow if restrictions are not imposed and a good chance that the restrictions would avert or at least mitigate that disaster.

The Government does not appear to believe it needs such a rationale. It seems to think that it’s legitimate to restrict millions of people’s lives on bases such as “on balance, that’s wise” or “to reduce pressure on the NHS” (not to avoid its collapse – just to make life a bit easier). That is a serious departure that MPs of good conscience should vote against. Otherwise it would be legitimate to introduce a curfew every evening to “reduce pressure on the police” or restrictions every time a new flu strain is identified “just in case” it might lead to a pandemic.

We did our bit. We got vaccinated. That has meant that, since April, the infection fatality rate of Covid has only been perhaps 3 to 4 times that of flu. Covid will be with us forever, killing tens of thousands each year. But since April it has never again been possible for it to create the waves of 100,000 and more deaths at a time that we experienced last Winter and that would have been much worse had we not accepted restrictions from last Spring onwards.

How many deaths would there be in an omicron wave? 50,000, perhaps? It can’t be greatly more than that, given the protection of the vaccines, unless the NHS is going to be completely overwhelmed (and no serious model yet shows that happening). But delta was going to kill perhaps 30,000 of us per year anyway, and we had no restrictions whatever for that. Everyone in the country was going to get delta over the next couple of years, as our immunity faded, unless we were willing to get boosters every few months forever. Why does it matter if we get omicron this Christmas instead? A vague sense that “Something must be done. This is Something. So let’s do This.” is not even close to an adequate basis on which to let Plan B proceed.