It worked once, it sorta worked twice, will it work again?

Last Friday, the Israeli army used a non-lethal sonic weapon to disperse Palestinians, and others, who were protesting/rioting in an attempt to disrupt the construction of a "security fence". It worked. Story here and here.

I'm in favor of further development and intelligent use of "non-lethal weapons", though I'm adamantly opposed to using them to disperse non-violent, non-distructive, and orderly protesters (if there is ever such a thing again).