Earlier quoted context omitted.
The context that's missing for a lot of the left leaning people hearing this is that much of the population of the US still sees police officers as heroes worthy of emulation. The thin blue line between order and chaos is a powerful image for a lot of people, and it doesn't necessarily have anything to do with being a punisher style police force.
Interesting perspective. Where I live we appreciate police but we do not see them as line that holds society from chaos. Is US this fragile?
IIRC, of the 50 most violent cities in the world, 17 are in Mexico.
This means that a lot more people who have seen grisly things (beheadings by cartels etc.) are present in the US, and this raises the awareness about what could also happen in the absence of a police force.