As Secretary for War (1905–12) he showed great organizational skill in his reforms of the British army. Recognizing the growing danger from German militarism, he used his knowledge of the German army to redevelop the military organization in Britain to meet the requirements of modern warfare. A small expeditionary force ready for instant action was formed with a Territorial Army as a reserve, and an Imperial General Staff to organize military planning on an improved basis. Haldane was sent on a mission to Berlin in 1912 to secure a reduction in naval armaments, but failed.