I find it funny how you understood and quoted the sentence.
Let me requote my interpretation which is differing by 100% from your view.
The Arab world has seethed whenever the United States used its U.N. veto – as it has done with frequency – to quash efforts to send international observers into the Palestinian territories or halt the construction of Israeli settlements.
I really wonder from where you took the Chuzpe to skip some important parts of the sentence.