Annan is like a company care-taker who is strictly bound to act within the limitations imposed by the board of directors.
Anything else requires the approval of the board.
Annan is not on the board, but still serves as a convenient punching ball when these same members of the board want to deflect critics.
When UN troops are sent somewhere they have a mandate, usually clear where it pertains to the aims, unfortunately often unclear when it pertains to the means. They have less rights than a US county sheriff though they are expected to do a lot more.
As a "peace keeping" mission, UNRWA was clearly doomed. All that were on the field knew at some stage that they were trapped.
The Rwandan warring faction did not mobilize half the country without it being noticed, the target was known, only the extent was underestimated.
The French authorities played an awkward role, no doubt about this, and they are probably the only ones that wrong or right, are not afraid to act further than the letter of their mandate, with or without UNSC
approval. (eg. Darfur, Ivory Coast)
This time they choose not, shame on them, but the biggest shame resides in the total inefficiency of the UNSC
and generally speaking the UN institution, which have little to do with human life but all with nations's best politics.