coal extraction is much more labour intensive than oil extraction.

fossil fuels being indispensable for the modern state, coal miners held leverage via their labour, and could have contributed to early "expansion of democratic rights". the modern worker on the oil rig has less leverage due to ease of automation of oil extraction.

post-war governments understood this difference in leverage, and this at least in part motivated the transition to oil.

The very materiality of coal is such as to enable and promote resistance to established orders. The processes through which it is mined and transported to the surface create an unusual degree of autonomy for miners; as Timothy Mitchell observes, ‘the militancy that formed in these workplaces was typically an effort to defend this autonomy’. It is no coincidence, then, that coal miners were on the front line of struggles for the expansion of political rights from the late nineteenth until the mid-twentieth century, and even afterwards. It could even be argued that miners, and therefore the economy of coal itself, were largely responsible for the unprecedented expansion of democratic rights that occurred in the West between 1870 and the First World War.

The materiality of oil is very different from that of coal: its extraction does not require large numbers of workers, and since it can be piped over great distances, it does not need a vast workforce for its transportation and distribution. This is probably why its effects, politically speaking, have been the opposite of those of coal. That this might be the case was well-understood by Winston Churchill and other leaders of the British and American political elites, which was why they went to great lengths to promote the large-scale use of oil. This effort gained in urgency after the historic strikes of the 1910s and ’20s, in which miners, and workers who transported and distributed coal, played a major role; indeed, fear of working-class militancy was one of the reasons why a large part of US aid to Europe, after the Second World War, went towards effecting the switch from coal to oil. ‘The corporatised democracy of postwar Western Europe was to be built,’ as Mitchell notes, ‘on this reorganisation of energy flows.’

— great-derangementpt. I