That was with the materials back then. Here are some of the current materials that we have that they didn't: 1. Concrete ( reinforced ) - much more durable th

That was with the materials back then. Here are some of the current materials that we have that they didn't: 1. Concrete ( reinforced ) - much more durable than brick and mortar. 2. Mechanized vehicles like backhoes and the such to build walls 3. Better materials to trap and retain heat. Probably others as well. We also now have a global warming problem and other externalities that make greenhouses' energy inefficiency bad for society. You know that "energy fetish"