France, and the European Union, have won a long diplomatic battle to host a €10bn (£6.7bn) international programme to develop a clean and almost limitless new form of nuclear energy.
World governments agreed yesterday that the Iter project - an attempt to re-create the energy at the heart of the sun - should be built at Cadarache, near Aix-en-Provence, in southern France.
If successful, the experiment, to be funded by the United States, the European Union, Russia, China, Japan and South Korea, will transform the energy, and ecological, outlook for mankind.
But in recent years the project has fallen victim to mankind's capacity for pettiness. Final agreement was held up by a battle between the French and Japanese over which country should host the main experimental site and test reactor. The US, after its quarrel with Paris over the Iraq war, supported Japan.
But a meeting of the six sponsors in Moscow yesterday decided to place the reactor in France. In return, Japan was promised 20 per cent of the construction contracts and 20 per cent of the 1,000 permanent research and administrative jobs at the site in Provence.
The decision was hailed by the French as proof that the European Union could deliver the goods for France - albeit too late to alter the Eurosceptic mood which rejected the EU constitution last month.
President Jacques Chirac, who will visit the existing atomic research station at the Cadarache site tomorrow, said: "This is a great triumph for France and Europe." He thanked the European Commission, other EU members, Russia and China for their "unflagging" support.
Iter - International Thermonuclear Experimental Reactor - will be the second largest international scientific project ever undertaken, after the International Space Station. The hope is that within 30 or 40 years the project will master a clean, cheap, safe and virtually inexhaustible form of energy by fusing atoms, rather than splitting them. In nuclear fusion, atoms are made to collide and fuse inside a reactor, releasing heat that can be harnessed to produce electricity.
But anti-nuclear groups and some scientists said that previous attempts to harness "fusion" energy had led nowhere.