Hamas's number one demand, above all other exports, is concrete and construction material - even before Cast Lead. They use it to build tunnels, barracks, and fortifications. Look at the tonnage of building materials received in Gaza and the results. Look at the monies received to build up infrastructure before Cast Lead and at the results.
Opposition leader Isaac Herzog calls on government to allow Syrian refugees into Israel (Haaretz)
from the article: Rights groups: World has betrayed the citizens of Gaza