This article is an editorial, which makes the case that fusion breeding (that is using fusion neutrons to breed nuclear fuel for use in conventional nuclear reactors) is the best objective for the fusion program. To make the case, it reviews a great deal of plasma physics and fusion data. Fusion breeding could potentially play a key role in delivering large-scale sustainable carbon-free commercial power by mid-century. There is almost no chance that pure fusion can do that. The leading magnetic fusion concept, the tokamak, is subject to well-known constraints, which we have called conservative design rules, and review in this paper. These constraints will very likely prevent tokamaks from ever delivering economical pure fusion. Inertial fusion, in pure fusion mode, may ultimately be able to deliver commercial power, but the failure to date of the leading inertial fusion experiment, the National Ignition Campaign, shows that there are still large gaps in our understanding of laser fusion. Fusion breeding, based on either magnetic fusion or inertial fusion, greatly relaxes the requirements on the fusion reactor. It is also a much better fit to today's and tomorrow's nuclear infrastructure than is its competitor, fission breeding. This article also shows that the proposed fusion and fission infrastructure, 'The Energy Park', reviewed here, is sustainable, economically and environmentally sound, and poses little or no proliferation risk.