From another thread KodiakBeer "The other thing that would have really hit the Germans hard (and not taken much force) would be to simply declare war on their proxy ally, Sweden. Bomb the Swedish merchant fleet into oblivion and the Germans suddenly have no steel or a host of other strategic materials that Sweden supplied them. You don't even have to occupy the country, just destroy their industry and fleet - always threatening to invade so the Germans have to send badly needed troops there." Probably not a good idea. Sweden did supply iron ore and other strategic materials to Germany and also in 1941 allowed the Germans to transport men, equipment and materials from Norway to Finland on their railways for the invasion of the Soviet Union, German soldiers on leave were also permitted to traverse Sweden. Sweden would probably not have been able to resist the Germans had the been invaded so they acquiesced to German demands. But, they also provided clandestine aid to the Allies during the war. 1) Sweden shared intelligence with the Allies. For instance, German telegraph traffic on lines leased from Sweden was intercepted and shared with the Allies. A Swedish math professor broke the German code. The Allies were also allowed to set up stations at locations from which they god monitor. German radio signals. 2) They helped organize and train Norwegian and Danish refugees to fight the Germans 3) 1944-45 allowed Allies to use air bases in Sweden/ Operation Where and When based at Luleå-Kallax Air Base in northern Sweden,a. clandestine air transport operation to Also "Operation Balder" which evacuated Norwegians, American internees of other nationalities from Sweden and transported airlifted Norwegian police troops. (refugee army) from Sweden to Finnmark. The air operations also shipped strategic freight, such as ammunition from Scotland to the underground in occupied Norway as well as communication equipment, Arctic equipment, and a hospital. 4) Part of the Swedish Merchant navy, which was outside the Baltic, worked for Britain 5) Sweden provided refuge for anti-fascist and Jews.
