What we think of when we see a bad neighborhood usually sticks in the present. We just see the gangs, the dilapidated housing, the food stamps, and be done with it — saying “This needs to change” without putting too much thought in how it started in the first place.
But in order to truly stop something, you have to prevent it. And preventing something involves looking at it from the very beginning. When we look at neighborhoods that become dilapidated, they usually become this way due to poor economic conditions — either companies begin to leave, or the economy gets bad, or some sort of major event occurs that causes a particular region or people to go under.
From here, people begin to develop certain habits. They begin to save less and spend more. They begin to commit crime to survive — small at first, but gradually increasing over time. These acts cause them to further fall into the pit. While in some instances, the growth of these actions on a community scale is small, other times they increase exponentially, and it is with these exponential increases that you get to the creation of long-term ghettos. What causes this exponential increase is something that needs further investigation, but is outside the scope of this article.
Once this behavior spreads far enough, it becomes commonplace. Once it becomes commonplace, it is taught — either formally or informally — to future generations. This is what causes these areas to linger for such a long time — not because of current conditions, but rather because past conditions have shaped the future.