Dave Saxton wrote:One of the rationales to the drive southward was to secure the oil fields there. Of course a secure source of oil was a long term imperative.
The Germans had a lot irons in the fire at that point. The Afrika Korps, the campaigns in the east, all the while the western Allies were building up with supplies and war materials traversing the Atlantic. This is where they ultimately needed to put more effort into.
There was I think a better option for gaining oil supplies than just diving into the Caucasus. While the Aftika Korps failed to notice why the desert wells were so frequently contaminated with unrefined oil (the Libyan oilfields!).
When Germany cajoled Hungary, Roumania and Bulgaria into the Axis in 1940/41 they missed a trick by not also roping in Turkey as well. German pentration of Turkey gives the Reich access to Iraq. Iran and to the south Kuwait and Saudi Arabia. The advantage is not only securing the Middle East oil supplies but also the opportunity for the Waffen SS to recruit sufficient Arab troops into several new SS panzer divisions...