What did Justus von Liebig mean by linking a country’s civilization to its sulfuric acid consumption?

In 1843, the German chemist Justus von Liebig famously stated that the measure of a country’s civilization could be determined by the amount of sulfuric acid it consumes annually.1

Liebig’s aphorism reflected the critical role of sulfuric acid as a foundational industrial chemical during the 19th century. Because sulfuric acid is essential for the manufacture of fertilizers—which were vital for increasing food production to support growing urban and industrial populations—its consumption served as a reliable proxy for a nation's level of industrial activity and economic development.12

Beyond agriculture, the acid was (and remains) a key raw material in numerous industrial processes, including petroleum refining, metallurgy, and the production of detergents, dyes, and explosives. Consequently, high consumption levels signaled a robust, technologically advanced economy capable of sustaining complex chemical and manufacturing industries.312