We are well and truly doomed. How in God’s name could it be cheaper to ship concrete from China than make your own. Every material, every tool, even food is becoming completely worthless.
I doubt they ship it in it’s finished form. More likely certain ingredients come from China and are mixed with things like sand and gravel here.
In the case of wheat gluten, the wheat was shipped from here, to China, and shipped back as gluten or in any number of other products.
Until recently, there were huge tariffs on cement from Mexico... So it is possible that cement and drywall were imported from China.