Well, it’s already happened in some parts of Australia - although it’s eased up now.
The very long, very harsh lockdown of Melbourne, Australia’s second largest city where I live - about 250 days in lockdown - was excessive and unjustified, given the level of threat.
Targeted interventions to protect small, particularly vulnerable populations in areas where health care is generally inadequate is something entirely different - and that’s what is happening in this current case.
Should the US not have quarantined cruise ship passengers on military bases for a while after they came back?