I was just giving a concrete example (pun intended). There’s still some rock crushing for aggregate, but the energy is mostly in cement. Concrete uses most of the cement, so it’s a good target. Japan uses something like four times the concrete of California, despite similar population, land area, and geography.
I've heard similar about concrete as well, but have had a difficult time putting it in context.
"Cement (3%): carbon dioxide is produced as a byproduct of a chemical conversion process used in the production of clinker, a component of cement. In this reaction, limestone (CaCO3) is converted to lime (CaO), and produces CO2 as a byproduct. Cement production also produces emissions from energy inputs – these related emissions are included in ‘Energy Use in Industry’."
Unfortunately, it doesn't further breakdown what percentage of the cement energy inputs contribute to GHG emissions.
