That's the root of the problem: the borders of movement are at the federal level* (well the 48 states), but the 'solutions' for non-integrated citizens are left to the states, counties, and local municipalities.

Informally, I recall learning that the 'solution' for inhuman insane asylums was to just release everyone and close them down. That's quite probably where a good portion of the 'homeless' problem comes from; there are of course also untreated veterans and just pure scam-artist pan-handlers.

The actual solution is also a difficult and politically impalpable issue:

    * national healthcare including drug addition treatment and mental health
    * an unending 'new deal'
    * + everyone trained to aptitude
    * + non-broken-window fallacy job assurance
    * adequate housing of actual quality near jobs

Also taxes / incentives (carrot+stick) at a federal level to pay for / encourage the correct behavior from all actors.

The various states have many powers that are reserved for independent nations elsewhere in the world, but interstate immigration control is not one of them. Freedom of movement is a Constitutional right, and there would be a huge bipartisan outcry if anyone tried to limit the movement of US citizens.

We don't, and legally we can't. Once they accept the ticket to SF and choose to make their home on the sidewalk, they become our problem, legally. And SF (even now) is so much nicer than Texas that few of the homeless are willing to go back.

And SF, like most cities, has this program which will send the homeless somewhere else.

http://hsh.sfgov.org/services/outreach-and-homelessness-prev...

Disputes between states are always political and only occasionally legal.

But yeah I can see it being difficult to prove, and harder to action. If one state wanted to sue the other, what is the process? Congress? Supreme court?

States do get into law suites with each other from time to time. The issue has to be about federal law.

Nebraska and Oklahoma vs Colorado was recently declined to be heard by the Supreme Court.

> That's an incredible story, especially from a Europe where immigration controls is on everyone's lips.

There's no immigration controls between the states because we're all part of the same country. Don't think it'd even be legal to try it, ever.

The only real "immigration controls" we have are for produce at the California border to control the immigration of insects, people are free to go wherever they want. Oh, and those annoying Border Control checkpoints not at the actual border to impede the movement of foreign nationals.