What are some problems that the Constitution did not resolve?

During the American Founding Period, the Constitution created by the Founders was their attempt to solve both internal and external problems afflicting the young nation. Internally, the nation required a stronger prerogative (and means) for revenue-generation and resolution of inter-state disputes, among other concerns. Externally, the ever-present threat of renewed war with Great Britain (not to overlook other foreign nations) demanded greater preparedness and efficiency that could only be served by a more powerful federal governing body.