Not to pat ourselves on the back to hard, but the reasonable state of today comes in part as a reaction to previous tragedy.
The expansion of government sponsored enterprises with organic police forces is concerning however. Examples in my mind are school districts, transit and other agencies without law enforcement as a core component or competency. To the extent that those forces are bound to the proprietary interests of the enterprise, the bounds of the monopoly are blurred.
https://en.wikipedia.org/wiki/Battle_of_Blair_Mountain
The British East India company’s operations are another example.