Lockdowns have never been a thing in our lifetime though. I'd say the priority should be stopping these very rare instances at source, but yes, having something in place ready to go would be good.I suppose it depends on what is going on around the world - we absolutely 100% need to have a vastly better track, trace and isolate system already in place so that lock-downs are very much the last rather than the only resort for effective containment.
Once we have it, I think to ensure that system (and the public's understanding of it) stays fit for purpose and regularly exercised using it over the winter for things like this and the flu would be the best use of it - in addition to keeping the system itself up and the deaths we'd prevent, we'd also probably find ourselves being a centre of excellence and it would support a whole load of useful skills and industries too.
I'm still not sure how you can realistically implement it though outside of pandemic scenarios. The trade off just isn't worth it for people.
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