Ranching and agriculture initially drove the Texas economy, but widespread oil production in the twentieth century dramatically changed the Lone Star State into a global industrial power. The US Energy Information Administration reports that the United States is now the world's largest crude oil producer, with Texas accounting for 40 percent of the nation's total.
The Texas Legislature first recognized the industry’s growing importance in 1917, expanding the authority of the Texas Railroad Commission to include oil and gas regulation. As the industry developed throughout the twentieth century, the agency gained considerable leverage over national regulatory policy and worldwide oil prices. Economic power thus produced immense political power, with many Texas politicians characterizing the federal government as an adversary to the state’s economic interests.