I've been pondering this question for a while. Title says it all. What will happen when there is no oil for the world's militaries? I mean an effective lack of oil, where nothing can be run, and there are no reserves, and no secret caches to be found. No oil, period.
I especially wonder what will happen to the air forces and navies.
Why just the world's armies? When the world runs out of oil, there will be no more conventional gasoline! No more petroleum-based plastics, no more giant energy plants...Imagine living Amish. That's what the world will be without oil. To prevent this, we'd have to quickly switch to sustainable energy. however, you need oil to manufacture solar cells, so screw solar. Hydro-power, yes. Geothermal, hell yeah. Wind-well duh. The first country to become completely sustainable (Norway) on non-oil sources will dominate the rest simply because they'll have electricity and we'll be burning candles.
Quite sure that the strongest countries will send armies at their border in order to asure that no other armies or rebels will use that lack of vehicles and things to attack the place and quickly create items that are indispensable for running everything up. Then, once the necessity can hold for a while, the researches would create few weapons/vehicles/ that are oil-free.
If I could manage everything, I'd order to bring more researchers for less time awaiting for new oil-free products and do temporary alliance with the countries that are known for using less oils on pretty much everything. E.g. that China has oil-free machines that create guns. I would just go and make an alliance with China until everything was back to normal, or sort of.
