It was a period in which Shell recovered very rapidly from the losses of the war and emerged as the second largest oil company in the world, despite many new challengers and competitors. Shell was one of the forces behind the hydrocarbon revolution. With the growth of the number of cars, trains, and planes the demand for transport fuels was enormous. Shell made the strategic decision to develop a petrochemical business and became a significant chemicals company. Chemicals became the second core business of the Group.