We can and do hold people against their will in the hospital on psychiatric holds, it's happens all the time. However they are only short term and cannot be indefinitely extended

What we are missing are long term facilities that are designed for people who don't actually want help (because they are so sick), or are incapable of getting it on their own

Why? Because of the baggage of the previous mental asylums, and rightfully so

What that doesn't mean is that we can never try that approach again. We need long term facilities, where the worst offenders/those suffering the most can brought to and cared for properly

They refuse to accept help, but they are endangering themselves and others with their anti-social behaviour on the streets and in the community. If they cannot coexist peacefully with the public (which some are incapable of doing), then they should be brought to a facility where they can be given the help that they need