It would be hard to imagine an economy developing without oil and natural gas, because it is the basis of every industrialized economy on Earth right now. Crude oil provides 97% of the energy for transportation (cars, trains, airplanes) in the world. In the US, oil and gas make about 20% of the electricity. In addition to that, think of all the things we make from oil: - plastics: just look at all the things made of plastic in front of you right now! - lubrication oils - petrochemicals for fertilizer, paint, preservatives, pharmaceuticals, cleaning chemicals, etc -fabric: most synthetic fabrics are based on petrochemicals So, try to imagine a country without all of these things. This would place you back in time more than 100 years in terms of technology.