I'm also constantly reminded that there was a counterflow brain-drain, from the US to Europe, both before and after WWII, largely of African-Americans fleeing o

I'm also constantly reminded that there was a counterflow brain-drain, from the US to Europe, both before and after WWII, largely of African-Americans fleeing oppression not just in the US South, but throughout the country. James Baldwin, Josephine Baker, Langston Hughes, Claude McKay, James Baldwin, Richard Wright, Nina Simone. Others who didn't necessarily emigrate to Europe did spend much time there: Paul Robeson, John Coltrane, Lillian Smith, Alain Locke, and Ethel Waters amongst them. You can also see patterns in movement of creative and technical talent within the US. There is of course the Great Migration from the South to northern, mostly industrial cities. California collected creative and technical talent from across the country, to a much greater extent than already established and notable Eastern states with large cities (New York, Massachusetts, Pennsylvania, ...). In some specific cases (the establishment of Hollywood), we know that lax patent enforcement and ready escape to Mexico was a strong draw for the early film industry against Edison's lawyers. I suspect that in addition to the much-ballyhooed physical climate, reduced social strictures, ease of land development, and rapidly-growing metro regions particularly near Los Angeles and the San Francisco Bay Area, contributed. There's also of course the WWII and post-war / Cold War military economy which played a tremendous role. You also saw organisations such as RAND moving wholesale to the West in the 1950s, for a combination of factors: more space, closer to major aerospace operations. Entire families were shipped west by railroad. My hypothesis is that intellectual and creative talent seek freedom, in both positive (opportunity) and avoidance of negative (oppression, suppression, abuse) senses. As much as we talk of capital being more mobile than labour, creative labour being concentrated in a few individuals is especially mobile, and quite sensitive to conditions of oppression. One obvious risk shares some parallels with a paradox of transportation infrastructure: as transportation improves, formerly greenfield / undeveloped regions become developed and land values explode such that further improvements in transportation become exceedingly expensive, both financially and politically. In the intellectual and creative realms, moats and ramparts, institutional rigidities, commercial and political allegiances, etc., emerge, which actively retard further progress. The challenge is in identifying where new regions (in the physical and geographic sense) of opportunity might be emerging.