Rebuilding cities is a local issue. The problem is the urban voters prefer democrats to run their cities. If this isn't a perfect example of insanity. Many urban areas are hell holes, the politicians promise to 'fix' it if they get voted in, people vote, cities remain crumby or get worse, wash, rinse, repeat....
Take New York City as an good example. NYC has been run by democrats since the end of the 2nd world war. In 1994 Rudy Giuliani was elected mayor. His broken window policy is credited with turning the city around. Violent crime in the city dropped as a result of this policy. The city became a better place to work and live. The broken window policy addressed minor crimes that were being committed and held those doing those acts accountable. Dems seem to have a distaste for law and order. But that distaste in policing will lead to more crime and further deterioration. The recipe for urban success has already been written, other cities just need to follow it. It's irresponsible for any big city mayor that doesn't improve it's citizens quality of life.