I don't know the breaking capacity of a typical U.S. C/B, but a lot of our domestic types are rated at about 6000A.
The utilities point out that in some cases (i.e. very close to a large xfmr) the short-circuit current for a residential supply can be as high as 16kA. Our regs. allow the lower-rated C/B to be used, so long as a suitable HRC (High Rupturing Capacity) fuse is used as backup. In practice, the PoCo main service fuse at the meter serves this purpose.
The old rewireable fuses (still in widespread use) are very bad on dead shorts, having a rated breaking capacity of just 2000A.
