The Saudi oil state armed to the teeth by the US and UK, addicted to oil and the most regressive type of Islam is the source.
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Traditional Salafism arrived in Gaza in the 1970s when Palestinian students returned from religious schools in Saudi Arabia. To this day Salafi groups in Gaza receive support from Saudi sources. According to Crisis Group, some, like the Ibn Baz Islamic society, are named after Saudi sheikhs. In the West Bank, the Palestinian Authority has allowed Salafi groups to receive funds from Saudi Arabia as well. Fatah and the PA hoped the Salafis could pose an Islamic counterweight to Hamas. Crisis Group reports: "Salafists have enjoyed the support of Fatah, which appointed them to PA institutions in an effort to compete with Hamas, and have voiced no opposition to the presidency of Mahmoud Abbas, whom they consider the wali al-amr (ruler)." As recently as last year, the PA reportedly appointed Salafi preachers to mosques in the West Bank.
The subset of jihadi or militant Salafis in Gaza includes four main groups: Jund Ansar Allah (Soldiers of God's Supporters), Jaysh Al-Islam (Army of Islam), Jaysh Al-Umma (Army of the Nation), and finally Tawhid wa Al-Jihad (Monotheism and Jihad), whose members were blamed for the killing of Vittorio Arrigoni. Although membership estimates vary widely, the jihadi groups are believed to include no more than a few hundred activists, mostly young men, some of them still in their teens. Two Hamas officials said these groups together number fewer than 100 members. Many of these adherents are recruited from the armed wings of Hamas and Islamic Jihad. An unknown further number of cadres within these larger factions have sympathy for the Salafis or may participate in Salafi armed action.
The jihadi Salafis are opposed to Hamas over two primary issues: implementation of Islamic law -- the jihadis want the imposition of a puritanical reading of sharia -- and ceasefires with Israel, which they oppose on principle. Tawhid wa Al-Jihad, the organization whose alleged members were blamed for killing Arrigoni, is said to be one of the smaller groups. According to Hamas and other Salafis quoted by Crisis Group, the group's leader, Hisham Sa'idni, is "more vehemently against Hamas than other Salafi-Jihadis." Saidini's first arrest by Hamas was followed by an escape, Crisis Group reports, during Operation Cast Lead, when Gaza's central prison was destroyed.