when was the last time an arab killed 100 arabs?
1). Lebanese Muslims and Christians killing each other;
2). Iraqi Arabs killing each other;
3). 110,000 dead in Algeria's civil war;
4). Hamas murdering anybody they dislike in Gaza;
5). Jordan killing thousands in "Black September";
6). Assad killing tens of thousands in Hama (Syria);
In numerous cases more than 100 Arabs were killed by another Arab in these conflicts, many of which are still going on. (Presumably, the genocide of hundreds of thousands in Darfur doesn't count, since it's Arabs killing non-Arab Africans.)
To that we need to add the "normal" secret-police disappearances, "honor killings", hanging of "traitors" who criticized the government or sold land to Jews, etc., etc., etc.
To get a bigger picture, and get an idea how many times we have Arabs killing 100 Arabs, let us look at the statistics.
On average, if you look at Muslim on Muslim violence, there have been about 11,000,000 Muslims killed in major conflicts by other Muslims since the creation of Israel in 1948, that source of all evil, as you yourself, who so succintly and intelligently condensed your knowledge of the Middle East into two words -- "zionism sucks" -- seemes to think.
As there have been only about 22,000 days or so since that time, it comes out to about 500 Muslims killed by other Muslims per day since then.
Arabs are about 20% -- perhaps a little less -- of the Muslims of the world. Assuming -- roughly -- that the violence is more-or-less equally spread, on an average it means about 100 Arabs killed by (presumably) other Arabs per day.
This is only a back-of-the-envelope rough calculation, but it's enough to show that the answer to your question, "when was the last time an Arab killed 100 Arabs"? Is probably "on average, yesterday".
