If we assume cats pee is the same concentration of salt as seawater, then its resistance is 0.2 ohms per metre.
If we assume the closest live and neutral get in the socket is about 1cm, then the resistance of the pee is 0.002 ohms.
At 110 volts, that would cause a current of 55000 amps.
Ok, so it could happen :-)
Don't they have fuses in the US?