How close to disaster did the British skate in April 1940? They started mining Norwegian territorial waters on 8th April 1940 (Operation Wilfred) with a plan to send forces to occupy Norwegian ports (Plan R4) if the Germans responded by invading Norway. OTL the Germans invaded Denmark and Norway on 9th April (Operation Weserübung) and Wilfred was forgotten.
Had Weserübung been postponed, what would have been the Norwegian response to Wilfred? Perhaps the Norwegians might have tried sweeping the British mines while laying their own fields parallel to their coast to make further British mining dangerous. Norway might also have tried to apply economic pressure on Britain by ordering their merchant ships not to visit British ports. In the absolute worse case might there have been clashes between British and Norwegian forces? If the Germans had not launched an invasion might the British have been provoked by some Norwegian action into launching Plan R4?
The consequences of no German invasion seem to vary from bad to very bad. If there is no immediate Norwegian reaction, Chamberlain is still PM when France falls and could argue that that was not his fault (there might be a naval battle off Dunkirk). At the same time in the USA, it is quite likely that Taft would win the Republican nomination with Scandinavian-American support. Chamberlain, who was a pessimist where America was concerned, would have likely assumed that America was going to desert him and felt that he must make peace. Britain would get no advantage from the mining because Norway would certainly react to clear the mines after June 1940. However, this all mild compared to the disaster of a strong Norwegian reaction. At the very least, London would have had to find a different source for its Christmas tree.
ps. As the Germans were reading some high level RN codes, one possible POD for a postponement of Weserübung might be decryption of a RN signal concerning possible German reactions to Wilfred. This might be interpreted as a plan to oppose Weserübung. Alternatively, a tanker could burn and sink in the Kiel Canal and prevent the transfer of ships from the Baltic.
Had Weserübung been postponed, what would have been the Norwegian response to Wilfred? Perhaps the Norwegians might have tried sweeping the British mines while laying their own fields parallel to their coast to make further British mining dangerous. Norway might also have tried to apply economic pressure on Britain by ordering their merchant ships not to visit British ports. In the absolute worse case might there have been clashes between British and Norwegian forces? If the Germans had not launched an invasion might the British have been provoked by some Norwegian action into launching Plan R4?
The consequences of no German invasion seem to vary from bad to very bad. If there is no immediate Norwegian reaction, Chamberlain is still PM when France falls and could argue that that was not his fault (there might be a naval battle off Dunkirk). At the same time in the USA, it is quite likely that Taft would win the Republican nomination with Scandinavian-American support. Chamberlain, who was a pessimist where America was concerned, would have likely assumed that America was going to desert him and felt that he must make peace. Britain would get no advantage from the mining because Norway would certainly react to clear the mines after June 1940. However, this all mild compared to the disaster of a strong Norwegian reaction. At the very least, London would have had to find a different source for its Christmas tree.
ps. As the Germans were reading some high level RN codes, one possible POD for a postponement of Weserübung might be decryption of a RN signal concerning possible German reactions to Wilfred. This might be interpreted as a plan to oppose Weserübung. Alternatively, a tanker could burn and sink in the Kiel Canal and prevent the transfer of ships from the Baltic.