Tzaar baalei chayim

The following paragraphs are excerpts from an article by Yosef Ben Shlomo Hakohen about tzaar baalei chayim(avoiding cruelty to animals).

"Rabbi Yochanan said that the prohibition against tzaar baalei chayim is a Torah prohibition, as it is written, 'For what reason did you strike your she-donkey these three times?' " (Cited in "Nefesh Kol Chai")

Rabbi Yehudah HeChassid, a contemporary of Maimonides, writes that we can learn the following lesson from the story of Balaam and his donkey:
"For every act by which a person needlessly causes pain to his friend, he shall be punished. This applies even if he needlessly causes pain to an animal. For example, if he overloads an animal and then, when it does not move, beats it - in the future he will be called to judgement before the Heavenly court, because inflicting cruelty upon animals is a Torah prohibition. Thus, concerning Balaam it is written, 'For what reason did you strike your she-donkey?' And in response to his having declared, 'If there was a sword in my hand I would kill you right now,' he himself was (later) killed by the sword." (Sefer Chassidim, section 666)

After reading the widely reported incident of President Obama swatting a fly, I went on the PETA website to see if they had published any posts regarding the incident. Sure enough, PETA addressed the incident.

I then checked as to whether any articles had been posted on their website regarding the thwarted terror attack in Gaza using booby trapped horses. I couldn't find any mention of the attack or condemnation of the use of the horses.

I wonder why

A horse is less important than a fly.