[_delirium]

That's definitely a possibility, but it's difficult to provide social services without having some sort of control over "immigration", which states and municipalities don't have. With no control over movements, a city offering particularly generous benefits will just get a lot of unemployed people moving there solely to get the benefits (a typical adverse selection problem). Countries mitigate this by having immigration screens that try to filter out people who are only moving there to collect welfare.

A possibility is to phase in benefits based on how long people have lived in a place (e.g. you get 10% of the max Pittsburgh city benefits for each year you've lived in Pittsburgh), but that would put a damper on labor mobility within the US, since people who moved around a lot would always end up with poor benefits (sort of like the old problem with non-portable pensions). And in any case the Supreme Court struck down Alaska's attempt to do that, so it isn't currently an option: http://law2.umkc.edu/faculty/projects/ftrials/conlaw/zobel.h...

If anything, I'd be more interested in going in the other direction in order to enhance intra-US mobility; it'd be nice if I didn't have to change health insurance just because I moved to a different state or got a new job, giving me the freedom to decouple my healthcare choices from other lifestyle choices.