It turns out that the UN is capable of strong language against Hamas - but only when it is the victim:
It is very rare for the UN to express "outrage" explicitly at Hamas. They did express outrage over rockets being stored in UNRWA schools but didn't blame Hamas explicitly, and in 2006 they said they were outraged at Hamas police stealing supplies from a UN warehouse.
“During a pre-announced demonstration, of which Hamas was well aware, a number of protestors climbed the perimeter wall and entered the compound causing damage to United Nations premises and property,” Mr. Serry said today in a statement from his office, UNSCO.
Due to precautionary measures taken, United Nations personnel working in the compound were fortunately unharmed.
The Special Coordinator noted with “deep concern” that, despite repeated assurances, the security forces in Gaza did not take the necessary and timely measures to protect UNSCO's compound.
“Pending a full transfer of security responsibilities to the legitimate Palestinian Authority, we continue to hold Hamas fully responsible for the security and safety of all United Nations personnel and operations in Gaza,” Mr. Serry said.
As this serious incident took place in the context of increasing incitement against the United Nations in Gaza, the Special Coordinator is conducting an urgent review of operations in Gaza.
So, in Israel and the territories, the UN only seems outraged when it is the victims of attacks. Even though the UN routinely expresses outrage over terror attacks worldwide, I haven't yet found any such expressions for Hamas' explicit policies of using Gazans as human shields, or their terror attacks or rocket fire against Israel.
Hamas reacted to this statement with derision:
Hamas prominent leader Salah Bardawil stated Wednesday that the UN resolutions by Robert Serry to halt aid provided for the victims of the Israeli aggression on Gaza had led to the popular anger the world witnessed Wednesday .
Bardawil said that claims of Robert Serry that Hamas holds responsible for the angry reaction of the refugees towards the United Nations staff are just " an attempt to jump over the reality ", pointing out that the masses wanted to tell Serry they reject the United Nations to be part of the siege imposed on the Gaza people .
" It would have been better for Mr. Serry to consider the serious repercussions of the UN decisions over reconstruction and adis for the victims of the latest Israeli aggression on Gaza, rather that distribution of accusations ." Bardawil added.