For well over fifty years now, bases in Germany have played an important role in the re-construction and eventual reunification of Germany after World War 2. From peacekeeping to helping the local economy, the various army bases that have been built up over the years across Western Germany continue to play an important role for stability in the region. In the last few decades many army bases have closed, but there continues to be a very strong presence of army installations in southern Germany.
At the close of World War 2, US and Russian forces scrambled to set-up bases in Germany. As you know, the country was pretty much split, with US Army bases springing up in Western Germany. As time passed, these bases in Germany flourished and became important to the reconstruction of Germany after the war. They also served as a deterrent for other nations thinking about trying to have more control in Germany. For these and many other reasons, army bases in Germany played a huge role in the development of Europe after World War II.
The army bases still in operation in Germany continue to play a big role, but that role is evolving. Other bases in Germany may close in the coming decades as the US Army concentrates on other regions in the world, but you can be sure that there are going to be some sort of army bases in Germany for many years to come. With a long list of army bases currently open and operating in Germany, it is easy to see why they're still in operation. Having been built up over a number of years, they have come to play an important part of keeping peace in the region.