Fear of a collapsing home-front due to the Allied bombing campaigns and that another "stab-in-the-back" at home could arise, as a result, caused Kaltenbrunner to immediately tighten the Nazi grip within Germany. From what historian Anthony Read relates, Kaltenbrunner's appointment as RSHA chief came as a surprise given the other possible candidates like head of the Gestapo, Heinrich Müller, or even SD foreign intelligence chief, Walter Schellenberg. Historian Richard Grunberger also added the name of Dr. Wilhelm Stuckart, the future minister of the German Interior as another potential candidate for head of the RSHA; however, he suggests that Kaltenbrunner was most likely selected since he was a comparative "newcomer" who would be more "pliable" in Himmler's hands.