Background

The cartoon was drawn in 1944 at a time when the Second World War was going very well for the Allies and rather badly for the Germans. The cartoon uses two important turning points in the war to make its point.

Stalingrad:

In 1941 Hitler had decided to invade the Soviet Union. This meant that Germany was now fighting on two fronts - in the West against Britain and in the East against the Soviet Union. A war on two fronts had never worked in the past, but Hitler was confident because he believed that the Soviet army was very weak and ill equipped. Hitler thought it would take 6 months to defeat the Soviet Union. It did not work. The battle took much longer and concluded in a German, not Soviet, defeat.
One of the key battles of the invasion of the Soviet Union took place at Stalingrad. For six months there was bitter street fighting and the whole city was reduced to rubble. As the Soviet winter of 1942 set in, thousands of German soldiers froze to death. They were also running out of food and ammunition. German soldiers eventually surrendered at Stalingrad in January 1943. The attack on the Soviet Union was a serious error for Germany. It was the biggest German defeat of the war so far. From that moment on, the Germans were in retreat and by December 1944 the Soviet army was ready to invade Germany itself.

Tunisia:

Tunisia marked the beginning of the Italian defeat by the Allies. Once again, Hitler made errors of judgement. First, he had declared war on the USA in December 1941. The first large-scale use of American forces was in North Africa and Tunisia, starting in 1942. Italy could not fight the combined forces of Britain and America on its own. The Germans came to Italy's aid. Hitler had made the mistake of believing Mussolini's boasts about the strength of his army. Finally, Italians and German forces were forced to surrender at Tunisia. Following this the Allies invaded Italy. Italy surrendered on July 1943. The German Army was on the run. By 1943, Hitler's judgement was increasingly failing him. He withdrew into his headquarters and concentrated on more military plans, having continual quarrels with his Generals.