The rocket fired from Sinai at the southernmost Israeli city, Eilat, was aimed equally at Cairo and Jerusalem.
The Egyptian military and the government of Israel have long had a common interest in maintaining order and fighting terrorism in Sinai. There were terrorist bombings in 2004 and 2006, and the Bedouin tribesmen have always had a strained relationship with the government in Cairo. Smuggling is the main economic activity of many Bedouin, and there are few economic alternatives for them (despite repeated promises from former President Mubarak over the years). Since the overthrow of Mubarak things have gotten worse, and in January a French tourist was killed by robbers in Sharm el-Sheik, Sinai's tourist Mecca (pardon the expression). Crime in the entire region has been growing, as has terrorism: For example, the pipeline carrying natural gas from Egypt to Israel and Jordan has been blown up an amazing thirteen times in the past year.