Complex sentence: However, the base is set to close in 2012 as it is no longer necessary to have a full time army base in Germany, as since the end of the Cold War there has no been no large enemy force capable of attacking Western Europe.
Split into simpler sentences: However, the base is set to close in 2012 as it is now no longer seen as necessary to have a full time army base in Germany. This is due to the fact that, since the end of the Cold War, there has no been no large enemy force capable of attacking Western Europe.