To lockdown or not to lockdown, that is the question

Closure? No closure? This type of closure? That type of closure?
I get asked what I think of a potential closure or lockdown. 
I do not know if a closure or lockdown is necessary or useful or effective or not. I am no expert and I therefore have no preference to this method over any other method.
In my opinion, if the experts decide that this is the only tool left in their toolbelt, or if this is the tool that will be most effective right now, that is fine by me.
But. But. But.
There is always a big ...