intervention in Somalia, often publicly expressed in quasi-Qutbist terms; and opposition to the internationally recognised Somali government, which, lacking a basis in religious (Sharia) law, is seen to lack legitimacy. Al-Shabaab hardliners broadly adhere to a Takfiri interpretation of the principle of al-wala' wal-bara' (), insofar as it prescribes dissociation from non-Muslims and those perceived as apostates. A major component of Al-Shabaab's ideology is Somali religious nationalism which is incorporated into its Pan-Islamist cause. Patriotic themes warning Somalis of the plots from international NGOs, "Christian Crusaders" (United States, Ethiopia, AMISOM) and their collaborators are a regular feature of the movement's propaganda. During the Ethiopian invasion of Somalia, Al-Shabab positioned itself as a staunch nationalist militia under the Islamic Muqawwama (resistance coalition) of the Islamic Courts Union, taking the most hardline stance against the invading "Christian crusaders". After the collapse of the ICU in 2007, Al-Shabaab launched its own independent insurgency, gaining popular support from Somalis for defending the country from American imperialism and foreign occupation. Al-Qaeda began enhancing its co-operation and support to Al-Shabab during this period, which enabled the movement to establish itself as the strongest military power in Southern Somalia. Al-Shabab regards Somalia's Federal Government as an illegitmitate "apostate" entity backed by foreign invaders. The group has persecuted members of Somalia's small Christian minority; accusing them of aiding the agenda of foreign "Crusaders" to "convert Somalis to Christianity". It has desecrated a Sufi mosque and graves on the basis that over-embellishing them into shrines is incompatible with Sharia, and has clashed with the pro-AMISOM Sufi militias of Ahlu Sunna Waljama'a. In addition, its statements have expressed anti-Zionist sentiments, and the group claimed that its 2019 DusitD2 complex attack was retaliation against the declaration of Jerusalem as the capital of Israel. Size and structure In 2017, observers estimated that al-Shabaab comprised between 7,000 and 9,000 fighters. In 2018, the Council of Foreign Relations and United States military revised this figure downwards, estimating 3,000 to 6,000 and 4,000 to 6,000 respectively. Reflecting an apparent al-Shabaab resurgence, the United States Africa Command estimated 5,000 to 10,000 fighters two years later, in 2020. Most recently, an expert report submitted to the United Nations (UN) Security Council in early February 2022 estimated that al-Shabaab's fighting force had grown to between 7,000 and 12,000 fighters. The group is led by a shura council of senior leaders, appointed and assigned portfolios by the emir, and