The Manhattan Project assembled the world's leading physicists in Los Alamos, New Mexico — a hastily built town in the desert — and gave them three years and effectively unlimited budget to build the atomic bomb. The geographic and intellectual concentration mattered more than any single hire. The thing that took decades on its own took three years together.
The principle: Some problems yield only to concentration — of talent, of attention, of decision-making. A diffuse effort spread across a dozen cities will be defeated by the same effort focused in one place, even at the cost of everything else.