Of course, its not the only factor, but I would argue it certainly is an important factor. This economic history book, Carbon Democracy, would also agree--it describes, in great detail, the methods by which the control of oil supplies played a key role in many of the additional factors you state.
In other words, most of the supposedly independent factors to the Keynesian postwar boom are themselves inherently dependent on maintaining control of the supply of global oil. Which in turns, means that there are strong incentives to preserve the types of authoritarian and repressive relationships that were developed between the West (mainly, the US) and countries in the Global South.