They claim responsibility for 26 Qassam rockets, two Grad missiles and 11 mortars today, yet even as the rockets are hitting near schools and shopping malls, Hamas is claiming that every single rocket and mortar is aimed at "military bases":
2008-12-24 Al Qassam Brigades fired seven mortars at the military base "Al Ersal"
2008-12-24 Al Qassam Brigades fired four mortars at the military base "Nir Oz"
2008-12-24 Al Qassam Brigades fired twenty four Qassam rockets at the military Bases near Gaza strip
2008-12-24 Al Qassam Brigades fired four Qassam rockets at the military site "Nitifot"
2008-12-20 Al Qassam Brigades targeted two military bases east of Rafah with (6) mortars
2008-12-13 Al Qassam Brigades targeted Zionist special force east of Khanyounis city
2008-12-08 Al Qassam Brigades targeted a military jeep east of Jabalya camp
2008-12-03 Al Qassam Brigades shelled the military site inside Nahal Oz base with two mortars
2008-12-03 Al Qassam Brigades shelled the Zionist military bases Huleet and Sofa with (6) mortars
2008-12-03 Al Qassam Brigades shelled the military base Nir Oz & the Third Eye with five mortars
2008-12-02 Al Qassam Brigades shelled Zionist soldiers east of Rafah city with (8) mortars
2008-12-02 Al Qassam Brigades shelled Zionist soldiers east of Rafah city with (5) mortars
2008-11-29 Al Qassam Brigades shelled Zionist military sites near Gaza with (10) mortars
2008-11-28 Al Qassam Brigades 5 mortars at the Zionist soldiers east of Khanyounis
This seems to be a relatively recent phenomenon. Earlier this year, Hamas was scolded by Al Qaeda leader Ayman Zawahiri (a medical doctor, Jimmy Carter would be gratified to hear) who was dismayed that "the blessed Qassam rockets don’t differentiate between a child and an adult, and moreover, perhaps [don’t differentiate] between the Jews and the Arabs and Muslims working in those colonies or in the streets and markets of Occupied Palestine, even though the Shari’ah forbids their killing."
Hamas responded that "Hamas doesn't mean to kill children by its rockets."
So even though the Hamas statements last month doesn't pretend that Sderot or Ashkelon are military targets:
2008-11-14 Al Qassam Brigades fired eight rockets at Sderot settlement, and even though their statements from a year ago are explicit that they are targeting "settlements" or "occupied towns," today they have changed their wording and call Sderot a "base" rather than a "settlement" and pretend that they target an armaments factory in Ashkelon.
2008-11-14 Al Qassam Brigades fired eight rockets at Sderot settlement
2008-11-05 Al-Qassam Fires Four Qassams at Asqalan
Hamas certainly does not want to be accused of violating Sharia law. If Muslims can credibly attack Hamas on purely theological basis, they are left with no reason to exist; they can no longer claim to be more moral than their rivals. So we see Hamas desperately spinning even their naked attacks on Israeli civilians as if they are Islamically halal.
Interestingly, as far as I can tell, every single Palestinian Arab killed by Israel in Gaza so far since November has been a member of either Hamas or Islamic Jihad - not a single civilian has been killed.