While in Italy, Philipp fell under the influence of Fascism, or otherwise believed the Bolsheviks to be a greater threat. On his return to Germany in October 1930, he joined the National Socialist German Workers' Party. In 1932, he joined the Stormtroopers (SA, commonly referred to as the Brown Shirts), and, the following year, his younger brother Christoph joined the Schutzstaffel (SS). Later, his two other brothers, including Wolfgang, also joined the SA. Through his party membership, Philipp became a particularly close friend of Hermann Göring, the future head of the German air force (Luftwaffe). In the Stormtroopers, he held the rank of Obergruppenführer.