Blunders of WWII: Hitler's Luftwaffe

At the beginning of the war, the Luftwaffe was the most modern air force in  the world.  They had investing many resources, and because of the Treaty of Versailles, all of the planes were newly built and modern, rather than old relics.  However, they failed their country on several occasions.  The fist major failure was their inability to annihilate the British and Allies at Dunkirk.  Much of the expeditionary force was able to make it back to England.  During the Battle of Britain, again the Luftwaffe failed to control the Royal Air Force, and consequently the invasion of England could not take place.  The industrial machine of Germany was not on a war footing.  Consequently resources were often scarce, and shared with other branches of the military.  Even within the Luftwaffe there was competition for resources.  ground troops, including parachute and anti aircraft guns too at least ten percent of the resources.  Consequently there were never enough resources.  This was especially felt in Russia.  After the invasion of Russia, the German resources were spread more and more thinly.  And when the Russians pushed the Germans back, the Russian industrial complex was out of reach of German bombers.  A great lack of the Luftwaffe was a good long-range bomber as the relied on dive bombing.  This lack crippled them in the end.  Experienced air pilots also became more scarce.  German pilots flew sortie after sortie until they were shot down.  Replacements lacked resources for training.  Consequently, as the war continued, the German pilots had less experience and training.  This became even more acute after an Allied bomber attack on German fuel supplies.  There was not fuel to spare for training.
The one think which could have evened the field for the Luftwaffe was the development of the jet.  The Germans had developed jet planes, which could fly 100 mph faster than any planes on the allied side.  However, Hitler wanted these planes to be fighter bombers, which delayed production, and so they had hardly no effect on the war.