[tech12]

Originally Posted by jd3189

Of course, this may not be the main reason, but it is interesting how so many cities, like Chicago, Detroit, Philly, Milwaukee, DC, Boston, SF, etc were far denser and populous at that point and many of them have yet to reach those peaks again.

SF was not denser and more populous in the 1960s.

SF population:
1900 - 342,782
1910 - 416,912
1920 - 506,676
1930 - 634,394
1940 - 634,536
1950 - 775,357
1960 - 740,316
1970 - 715,674
1980 - 678,974
1990 - 723,959
2000 - 776,733
2010 - 805,235
2020 - 873,965

edit: SF's population first boomed after the gold rush. There was constant growth after that, some stagnation during the great depression, and then another WWII/post-war boom (shipyard workers/2nd great migration, increased Asian and Latin American immigration, etc). Then there was a 1960s-1980s population decline caused mostly by the combo of de-industrialization (shipyards closed down, for example) and the suburban boom, and white flight in reaction to the new post-WWII black neighborhoods (which were by that time declining too, due to poor conditions from stuff like the war on drugs/neglect by the government/corrupt public housing management/racist redevelopment schemes, not to mention rising housing prices due to gentrification and SF's constant lack of housing), and to the quickly rising number of Latin American and Asian immigrants. Immigration from Latin America and Asia has continued to fuel SF's population growth since then, as the white and black populations decline.