Quisling's party experienced a rise in membership to a little over 30,000, but despite his optimism it was never to pass the 40,000 mark. On 5 December 1940, Quisling flew to Berlin to negotiate the future of Norway's independence. By the time he returned on 13 December, he had agreed to raise volunteers to fight with the German Schutzstaffel (SS). In January, SS head Heinrich Himmler travelled to Norway to oversee preparations. Quisling clearly believed that if Norway supported Nazi Germany on the battlefield, there would be no reason for Germany to annex it. To this end, he opposed plans to have a German SS brigade loyal only to Hitler installed in Norway. In the process, he also toughened his attitude to the country harbouring the exiled king, the United Kingdom, which he no longer saw as a Nordic ally. Finally, Quisling aligned Norwegian policy on Jews with that of Germany, giving a speech in Frankfurt on 26 March 1941 in which he argued for compulsory exile, but warned against extermination. In May, Quisling was shattered by the death of his mother Anna, as the two had been particularly close. At the same time, the political crisis over Norwegian independence deepened, with Quisling threatening Terboven with his resignation over the issue of finance. In the end, the Reichskommissar agreed to compromise on the issue, but Quisling had to concede on the SS issue: A brigade was formed, but as a branch of the Nasjonal Samling. Meanwhile, the government line hardened, with Communist Party leaders arrested and trade unionists intimidated. On 10 September 1941, Viggo Hansteen and Rolf Wickstrøm were executed and many more imprisoned following the milk strike in Oslo. Hansteen's execution was later seen as a watershed moment, dividing the occupation into its more innocent and more deadly phases. The same year Statspolitiet ("the State Police"), abolished in 1937, was reestablished to assist the Gestapo in Norway, and radio sets were confiscated across the country. Though these were all Terboven's decisions, Quisling agreed with them and went on to denounce the government-in-exile as "traitors." As a result of the toughened stance, an informal "ice front" emerged, with Nasjonal Samling supporters ostracised from society. Quisling remained convinced this was an anti-German sentiment that would fade away once Berlin had handed power over to Nasjonal Samling. However, the only concessions he won in 1941 were having the heads of ministries promoted