  Embedded in the historical context, we review recent progress in the
development of nucleon-nucleon (NN) potentials based upon chiral effective
field theory. A major breakthrough is the construction of the first NN
potential at next-to-next-to-next-to-leading order (fourth order) of chiral
perturbation theory (ChPT). The accuracy of this potential concerning the
reproduction of the NN data below 290 MeV lab. energy is comparable to the one
of phenomenological high-precision potentials. Since NN potentials of order
three or less of ChPT are known to be deficient in quantitative terms, the
recent advances show that the fourth order of ChPT is necessary and sufficient
for a reliable NN potential derived from chiral effective Lagrangians. This
recent substantial progress raises hopes that we might be getting closer to a
solution of the nuclear force problem at low energies that has plagued the
community for more than half a century.
