As has been discussed here before, the US and other western nations are not going to lock down cities in the same way as Wuhan has.
Wuhan does appear to have contained the virus (or, at the very least, stemmed the flow of information...) and kept the infection rate at a very low level (0.5%, or about 60,000 cases) - but seasonal flu (which has a comparable level of contagiousness) affects between 3 and 13% of the entire US population every year - if we can expect a similar range for SARS-CoV-2, that means between 6 and 30 times higher infection rates than in Wuhan.
As
@Famine pointed out, a 0.5% infection spread would translate into 247k hospitalisations (with a capacity around 300k)... but a flu-like spread (as is being alluded to by Trump and many others) would mean
1.5-7.5 million hospitalisations... even over a whole year that would be a very serious problem.