Then is it safe to say that your critique doesn't extend to smaller cities with democratic leadership? In which case, we'd only be discussing larger cities. Some of the safest smaller cities in the U.S. have democratic leadership.
Fine, but this is a correlation and not a causation. Many larger cities (i.e. cities large enough to have "inner cities") have had crime issues that precede their democratic leadership, and in some cases crime has been worse under republican leadership than under democratic. I don't think democratic leaders necessarily have the interests of poor neighborhoods in mind, but it's absurd to trace the root cause of violence in American cities to democratic leadership.
Here's a list from CBS from some time within the last 2-3 years. Top ten most violent cities:
https://www.cbsnews.com/pictures/the-most-dangerous-cities-in-america/32/
1. St Louis: Democratic mayor since 1949.
2. Detroit. Democratic mayor since 1962.
3. Baltimore: Democratic mayor since 1947, with a 4 year break from '63-'67.
4. Memphis: Democratic mayor since 1991.
5. Little Rock: Democratic mayor at least back to 1979, hard to track back farther than that.
6. Milwaukee: Democratic mayor since 1960.
7. Rockford(Ill.): Dem mayor at least back to 1989 (difficult to see farther), although a break for an "independent" from '05-'17. Current mayor Dem.
8. Cleveland: Democratic mayors going back to 1942, with a break from '72-'77 and '80-'89 for Republicans.
9. Stockton: Mix.
10. Albuquerque. Current Dem mayor, Repub mayor from 2009-2017, and then all Dem going back to 1985.
Finding a "Republican run" city at a given year that "has crime" isn't even close to meeting the example of places like Baltimore.
Sure, correlation might not be causation. Wonder what a possible mediating variable is between electing Democratic leadership for a generation or more, and high crime, in major cities?