It can not be denied that the Jihadi Militants of Hamas are violent thugs, but that Israel currently has appropriate countermeasures for Hamas' rockets and has been implementing those countermeasures for years can also not be denied. The rationale for the current incursion and spate of Palestinian non-combatant deaths is that the Israeli civilian population is in danger, though not yet victim to actual violence, the hypothetical scenario where the Iron Dome fails to protect the Israeli civilian population seems to be falsely equalized to the actual death toll in Gaza. Rather than Israel being satisfied with tenuous stalemate (where Hamas flings hundreds of rockets at Iron Dome to no avail), Israel has elected to escalate the conflict and and to kill non-combatants who have no where to go within the densely populated Gaza Strip. While Israel justifies the 450+ deaths to Hamas' use of "human shields" would be akin to Eco terrorists intending to bomb David Koch's Park Avenue apartment but demolitioning Spanish Harlem instead only to justify the fact that David Koch engineered his proximity to those in Spanish Harlem as a defense. Other than those who blindly defend Israel, the rest of the world can see through the twisted argument and the culpability of the civilian deaths are exactly upon those that commit the action of bombing and shooting missiles and not the Hamas flailing against Israel's Iron Dome.
Every action has repercussions, and yes Hamas' rocket attacks make them one of the bad guys in the conflict, but it doesn't relinquish Israel of accountability of its actions and the deaths it wrought on a population that despite most warmongers' assumptions aren't in fact all Hamas militants.