Discussion: Homelessness and Mental Illness

Over the past few weeks, I came across a few YT channels containing interviews with homeless people in various north American cities. After listening to some, it becomes obvious that a lot of these people have some combination of serious mental illness, drug addictions, nonexistent family and inadequate social safety net. The willingness of certain large cities, to tolerate these people without actually trying to help them makes things worse. And this brings me to another question- why is the homeless problem in American cities much worse than in other developed countries- especially those in western Europe? And if this problem is due to systemic reasons and long standing trends- why has it become so much worse in past 10-15 years?

and here is another one- from a different city.

What do you think? Comments?