  It is shown that violation of the Born Rule leads to a breakdown of the
correspondence between the quantum electromagnetic field and its classical
counterpart. Specifically, the relationship of the quantum coherent state to
the classical electromagnetic field turns out to imply that if the Born Rule
were violated, this could result in apparent deviations from the energy
conservation law applying to the field and its sources (Poynting's Theorem).
The result suggests that the Born Rule is just as fundamental a law of Nature
as are the conservation laws.
