His analysis has some valid points, but is heavily colored by his “progressive” world view. He ignores inconvenient facts to make it fit.
A glaring example is placement of Louisiana with a high murder rate, in the “Deep South” when most of the killing in Louisiana occurs in the part that he assigns to “New France”.
He also creates a new term that I do not see elsewhere in the literature “assault deaths”. I do not see it defined.
He mentions New Hampshire, Minnesota, and Maine as having the lowest rate of “assualt deaths”. I assume that he means murders and manslaughters.
But North Dakota has had a lower rate for decades (recently bumped up by the oil boom), and Utah, in the “Far West” has also been as low or lower than Maine in many years.