This has always stuck with me. When I was a lot younger, in the early 90s I was dating a guy who was pretty high up in Washington state's DSHS. I remember him saying that massive cutbacks were forcing all the institutions they had left to close. I asked him naively what the plan was for everyone who was going to be released and he said "Nothing. There is no plan. There're just going to live on the streets."

I was aghast and assumed he had to be wrong somehow. Fast forward ten years and downtown Seattle is full of homeless people. Fast forward to today and multiple cities are basically overrun with them, when the population of them was tiny just 20 years ago.

I hate feeling old and partisan but my personal experience leads me to believe this is the crazy GOP policies of the 80s coming home to roost. It's certainly the most likely explanation given what I know and doesn't require some of the mental backflips necessary for other explanations.