Although there were a few small oil mines in these countries, they were consumed very quickly because of the suppression all the time.
By now, the output of oil in those countries had been much lower than the consumption.
Under the joint restriction of other countries, the amount of oil that really fell into their hands was not enough to offset their annual consumption in this regard.
However, oil was a kind of energy. It could be used in some civilian vehicles, and now all large-scale military weapons. They needed oil to drive their energy.
If a country lost strategic resources like oil, its military strength would also plummet, unable to compete with other countries.
Even the transportation of a country would be paralyzed, with all kinds of problems involved.
At that time, not only the foreign invasion but also the citizens of this country would be dissatisfied with it.