IZA, a German-based think-tank, came out with a study worth pondering:
Our results do not support the notion that suicide attacks and targeted killings follow the “tit-for-tat” pattern that is commonly postulated in the literature.
One example of an event erroneously reported as “tit-for-tat” was the 2002 bombing at Hebrew University, which the MSM described as a Palestinian revenge for the targeted killing of Hamas terror leader Salah Shehadeh.
(Hat tip: Daniel Finkelstein)
