Germany was permitted a civil defense force. It was explicitly forbidden an army offensive capabilities. The abolition of the General Staff was a critical part of that, because the senior officers in any army, the product of generations of training and experience, is something that would be extraordinarily hard to reproduce. The Allies didn't merely want to hamper Germany's ability to wage war, they wanted to actively terminate it. The Weimar government, by very quietly breaching the Treaty as regards to the General Staff, by calling them "civil servants" and then giving them the space and the time to pick up the pieces and begin planning for the next war, ultimately handed Hitler not only the expertise to wage another war, but the actual plans for waging that war.