I disagree. Almost every country on the planet arms its police force and all of those countries are rather low in crime, at least compared to the US.

When there's a situation that requires guns, they stay put until the police with the guns arrives. Or they become a hero and get stabbed in the process:

https://www.theguardian.com/uk-news/2017/mar/22/police-briti...

https://www.bbc.com/news/uk-england-london-49273979

https://news.sky.com/story/police-officer-critical-after-bei...

https://www.standard.co.uk/news/crime/man-charged-stabbing-p...