David Frum is extremely frumpy that the folks attempting to break the three year long Israeli blockade of Gaza were delivering... cement,
This a curious matter over which to fall off one's chair in shrieks of indignant rage - Hamas can barely launch rockets at empty fields, they're not going to catapult whole bunkers across the Erez Crossing - but I nevertheless have to agree with Frum, they shouldn't be trying to deliver cement to Gaza. Anything built with it would just be crushed inevitably back into dust:
On December 27, 2008, Israel launched what it called Operation Cast Lead. ... the fighting destroyed 3,540 housing units in Gaza and 2,870 sustained severe damage ...
... wartime attacks destroyed public and service sector infrastructure, including government buildings, bridges and 57 kilometers of asphalt roads (and other roads), and damaged 107 UNRWA installations, almost 20,000 meters of pipes, four water reservoirs, 11 wells, and sewage networks and pumping stations. ...
... on January 3, the first day of the Israeli ground offensive, Israeli attacks "damaged and put out of commission seven of the 12 electrical power lines that connect Gaza to Israel and Egypt." On January 13, Israeli aircraft bombed a warehouse containing spare parts needed for repairs to the grid that it had recently allowed Gaza's utility, GEDCO, to import ...
The military offensive destroyed 18 schools (including eight kindergartens) and damaged at least 262 other schools. ...
The war destroyed 268 private business establishments in Gaza and damaged another 432 ... 324 factories and workshops were damaged or destroyed during the war...
The construction materials sub-sector was particularly devastated. ... all seven of the factories we examined, every vehicle on factory grounds had been demolished, and many buildings and other pieces of equipment had been damaged or destroyed. A preliminary survey of the damage to Gaza's industrial sector reported in February that the war destroyed or damaged 22 of Gaza's 29 ready-mix concrete factories, causing an "85 percent loss in the sub-sector's potential capacity"...
Israel's military offensive resulted in an estimated $268 million in losses to the agricultural sector. This includes $180 million in direct damage during the war to fruit, grain and vegetable crops, animal production, and infrastructure like greenhouses and farms ... "almost all Gaza's 10,000 smallholder farms suffered damage and many have been completely destroyed"...
Foreign Minister Tzipi Livni reportedly stated on January 12, 2009, that "Hamas now understands that when you fire on [Israel's] citizens it responds by going wild, and this is a good thing." Livni said on January 19, 2009, the day after the conflict ended, that "Israel demonstrated real hooliganism during the course of the recent operation, which I demanded." Deputy Prime Minister Eli Yishai said at a conference on February 2, 2009 that "we have to determine a price tag for every rocket fired into Israel," and recommended that "even if they fire at an open area or into the sea, we must damage their infrastructures and destroy 100 houses."
I would suggest building bunkers next time, though, instead of apartments. It would be much safer.