Would the previous host have it again or would it simply not be held?
Google did not yield results.
I think instead they would pick a random city, or request hosting of the city.
The world is gonna make sure the Olympics isn't postponed(don't know if it ever has).
The Olympics have been cancelled three times.
1916
1940
1944
I don't foresee it happening anytime in the near future and if it does I'll assume they just wouldn't have it.