There’s no full lockdown in the US. Even in hard hit states like Michigan, grocery stores, doctors etc and essential services as defined by state governments are open.
You simply can’t do a total lockdown because you’re going to cause panic both before the lockdown is announced with a rush on stores and people hoarding and you’re going to cause panic after a lockdown starts as people become desperate and start running out of essentials.
Even the idea of reducing store hours (as Sindh government announced) is a bad one because you’re going to compress everyone that goes out to buy things into a smaller time period and therefore create larger crowds (which will increase the risk of infections) during the reduced business hours.
So what do you suggest ? Partial lockdown is not the way forward and full lockdown is not feasible.If US is not doing then at least UK is going for it.US should not taken as a good example as the reported cases and casualties are on the higher side too.