General Robert E. Lee had several strategies for winning the independence of the Confederacy. In order to do this Lee focused on several ways of doing this. Foremost was Lee's expertise in creating fortifications protecting key Southern supply depots and important Southern cities. This allowed, as example the ability of Vicksburg to repulse attacks upon it.
Lee also was of the school that encouraged a large mass of troops to concentrate on a Union position. The risk was leaving parts of the South less protected but on the other hand, the tactics of this idea was a sound one.