The rest of the world still has only about 1/8 the number of cases that China has, but China's cases appear to be levelling off, while everywhere else is just starting to climb. That's what I meant by quarantine being too late.
Now, each country can have domestic quarantines that keep people from infected towns away from uninfected towns, but as a long term tactic, that's doomed. From what I've heard, in the US, a judge allowed someone to leave quarantine who was later found to be infected. https://nu.federati.net/attachment/264824