But previously, we learned that they played a part in digging the foundations and the basement. That excavation is still (in effect) “in use” in the currently renovated White House. This is a “Ship of Theseus” argument (https://en.wikipedia.org/wiki/Ship_of_Theseus) and it’s ridiculous. I like this quote from Douglas Adams: “The idea of the building, the intention of it, its design, are all immutable and are the essence of the building. The intention of the original builders is what survives. The wood of which the design is constructed decays and is replaced when necessary. To be overly concerned with the original materials, which are merely sentimental souvenirs of the past, is to fail to see the living building itself.”