Allied strengths:

While Hitler faced increasing economic difficulties after 1942, the resources of the Allies grew stronger: the USSR's economy rapidly transformed into a wartime economy and Russia was producing more armaments and better -quality armaments than Germany by 1943. The centralised state economy of the USSR proved more able that Hitler's Nazi state to produce what was needed to fight a prolonged war and the US also overtook Axis powers in terms of production

The Allies were able to turn greater economic strength into effective fighting power and learned from mistakes of 1941 to increase the effectiveness of their combat forces:

• they improved the quality as well as quantity of military forces and technology
• they made sure there were excellent back-up services providing support and supplies to the troops
• they set up  a large civilian apparatus to support the Allied forces, which allowed them to mobilise their economic, intellectual and organisation strengths of the purpose of waging war

Strategic decisions were key  e.g. focusing firstly on defeating Germany rather than Japan and the strategic bombing campaign which weakened Germany's ability to fight effectively and meant they had to divert funds into an anti-aircraft strategy

Weakness of Axis powers

By not committing Germany's full military capacity to the invasion of Britain in 1941, Hitler allowed Britain to survive. This meant that Britain kept the war going in the West, in the Atlantic and Africa; it was also the launching pad for the second front.

The invasion of the Soviet Union was a huge mistake; Germany then had to fight on two fronts

Declaring war on the US was a major error ; the USA's entry into the war allowed the Allies to invade Italy, carry out devastating raids on Germany and open up the Second Front in 1944

Hitler's personal conduct of military operations was disastrous; this can be seen most clearly in the USSR . Another serious mistake was to concentrate on producing V-rockets when Germany could have been developing jet aircraft which might have restored German air superiority and weakened the Allied bombing campaign of 1944 - 45

Hitlers' mistakes meant that the war when on much longer than he had expected and Germany increasingly suffered from material shortages as the war continued

The home front was not as effective; women were not employed in munitions factories until late in the war. The German military resented and rejected interference and direction from civilians which prevented any useful collaboration between civilian and military experts.