> Except in Hong Kong, Singapore, Taiwan, or (more arguably) Japan. And South Korea, while they had a rougher early outbreak, seems to have gotten a lid on the disease now.

And how long can they keep strict containment in force, and what happens when it lifted? You're speaking as if China or SK are now magically immune from a second wave as soon as they relax their restrictions.

they're building testing capacity to test everybody arriving in the country.

Good for them, lets see how long that takes and how effectively that works at a pre-epidemic scale, and over the long term.

Surely that’s not a viable long term solution?

it's the most viable until a vaccine comes, so why not?

> he science isn't unsound

In this case the science is flat out unsound: There are several coronaviruses known to infect humans. None are known to result in lasting immunity, and some are known to not result in lasting immunity. This is one of the challenges in making a vaccine.

Given the observed hospitalization rates, many millions in the UK will require hospitalization due to corona. At the moment, their hospitals could support merely thousands. We know from other cities that the mortality rate (particularly among younger people) is dramatically higher when adequate medical care is not available.

Under the UK's argument, the worst outcome of aggressive mitigation is that you are actually successful at it and achieve containment which just shifts the infection later in time at a high economic cost. Given the existing known infection rates in the UK that seems unlikely at that point, but even if it were to happen it would provide time to ready treatment facilities and allow for the discovery of more effective and/or scalable treatment techniques.

Fortunately, the UK has been backing off from its initial position and has now been recontextualizing their position as 'mitigate as much as possible'-- which is what pretty much all of the west is doing.