The circuit breaker is a bi-metallic device, much like the Constant Voltage Regulator. However, if it sees a current greater than 10 amps, the metal inside bends and creates an open circuit, not allowing any current through. When the demand drops, it should return to normal.
However, these things are notorious for not being terribly reliable, and your's is now likely an open circuit. Time to replace it.
Do not bypass this safety device, as this is your only fuse for the foglamps. Should you draw enough current, the carrying capacity of the wires may be exceeded and not only will the Smoke Genie be let out, your local firemen will have an emergency call to your car.