The fight over crude oil, an especially useful natural resource, can sometimes compromise world peace. However, it can be cheaply produced from sawdust (or trees chopped into sawdust).
Step 1: Sawdust is heated in the absence of air. This is called destructive distillation:
Sawdust --(heat)----> Charcoal (C) + Wood Tar + Wood Gas + Acetic Acid + Acetone + Methanol + Water Vapor
The wood gas is similar in composition to the natural gas obtained from oil drilling, as the wood tar is similar in compostion to tar obtained from oil. The acetic acid, acetone, and methanol are tapped off as valuable by-products. The charcoal is used to create the liquid part of the crude, using the synthesis gas reaction and the Fischer-Tropsch Process:
C + H2O --strong heat---> CO + H2
CO + H2 --(iron and cobalt catalysts, heat)---> liquid alkanes, alkenes, and alcohols + water vapor + carbon dioxide
This process can also use coal as the feedstock; coal can be destructively distilled just like wood. As a bonus, ammonia is also produced when using coal as the feedstock. However, wood is renewable, while coal is not.