  Diffractive hard scattering is interpreted as the effect of soft gluon
exchanges between the emerging energetic quarks and the nucleon's color field,
resulting in an overall color singlet exchange. Summing multiple gluon
exchanges to all orders leads to exponentiation and an amplitude in analytic
form. Numerical evaluation reproduces the precise HERA data and gives new
insights on the density of gluons in the proton.
