By the end of 2015, its self-declared caliphate ruled an area with a population of about 12 million,[115][116][161] where they enforced their extremist interpretation of Islamic law, managed an annual budget exceeding US$1 billion, and commanded more than 30,000 fighters.

[162] After a grinding conflict with American, Iraqi, and Kurdish forces, IS lost control of all its Middle Eastern territories by 2019, subsequently reverting to insurgency from remote hideouts while continuing its propaganda efforts.

[171] Under its rule of these regions, IS launched genocides against Yazidis and Iraqi Turkmen; engaged in persecution of Christians, Shia Muslims, and Mandaeans; publicised videos of beheadings of soldiers, journalists, and aid workers; and destroyed several cultural sites.

This name has been widely used by ISIL's Arabic-speaking detractors,[184][187] for example when referring to the group whilst speaking amongst themselves, although—and to a certain extent because⁠—it is considered derogatory, as it resembles the Arabic words Daes ("one who crushes, or tramples down, something underfoot") and Dāhis (loosely translated as "one who sows discord").

[190] The group's declaration of a new caliphate in June 2014 and its adoption of the name "Islamic State" have been criticised and ridiculed by Muslim scholars and rival Islamists both inside and outside the territory it controls.

Qutb's doctrines of jahiliyya (pre-Islamic ignorance), hakimiyya (divine sovereignty), and takfir of entire societies formed a radicalized vision of the Muslim Brotherhood's political Islam project.

IS ideologues rarely uphold adherence to Islamic scholarship and law manuals for reference, mostly preferring to derive rulings based on self-interpretation of the Qur'an and Muslim traditions.

[245] Security and intelligence expert Martin Reardon has described IS's purpose as being to psychologically "break" those under its control, "so as to ensure their absolute allegiance through fear and intimidation", while generating "outright hate and vengeance" among its enemies.

Advising al-Baghdadi were a cabinet of senior leaders, while its operations in Iraq and Syria are controlled by local 'emirs,' who head semi-autonomous groups which the Islamic State refers to as its provinces.

[266] In August 2016, media reports based on briefings by Western intelligence agencies suggested that IS had a multilevel secret service known in Arabic as Emni, established in 2014, that has become a combination of an internal police force and an external operations directorate complete with regional branches.

[268][269] U.S. President Donald Trump stated in a televised announcement that Baghdadi had, in fact, died during the operation and that American forces used support from helicopters, jets and drones through airspace controlled by Russia and Turkey.

[286] The United Nations Commission on Human Rights has stated that IS "seeks to subjugate civilians under its control and dominate every aspect of their lives through terror, indoctrination, and the provision of services to those who obey".

[310] IS publishes material directed at women, with media groups encouraging them to play supportive roles within IS, such as providing first aid, cooking, nursing and sewing skills, in order to become "good wives of jihad".

[313] In a document entitled Women in the Islamic State: Manifesto and Case Study released by the media wing of IS's all-female Al-Khansaa Brigade, emphasis is given to the paramount importance of marriage and motherhood (as early as nine years old).

Lafarge, which merged with Holcim in 2015, agreed to pay $778 million in forfeiture and fines as part of a plea agreement not to be convicted and sentenced to prison for providing material support to a terrorist organization.

[343] IS received pledges of allegiance and published media releases via groups in Somalia,[344] Bangladesh,[345] Indonesia, Myanmar,[346] Thailand[347] and the Philippines,[348] but it has not announced any further official branches, instead identifying new affiliates as simply "soldiers of the caliphate".

"[365] Abd al-Aziz ibn Baz, the former Grand Mufti of Saudi Arabia, also stated that Kharijites are not Muslims, saying: "the majority are of the opinion that they are disobedient and misguided innovators, though they do not deem them unbelievers.

Referring to the "self-described 'Islamic State'", the letter censures the group for carrying out killings and acts of brutality under the guise of jihad—holy struggle—saying that its "sacrifice" without legitimate cause, goals and intention "is not jihad at all, but rather, warmongering and criminality".

[374] Citing the Quran, he stated: "The punishment for those who wage war against God and his Prophet and who strive to sow corruption on earth is death, crucifixion, the severing of hands and feet on opposite sides or banishment from the land.

[383][better source needed] According to The New York Times, "All of the most influential jihadist theorists are criticising the Islamic State as deviant, calling its self-proclaimed caliphate null and void" and they have denounced it for its beheadings of journalists[384] and aid workers.

Al-Zawahiri called upon ISIL members to close ranks and join al-Qaeda in fighting against Assad, the Shia, Russia, Europe, and America and to stop the infighting between jihadist groups.

While there was talk about 'radical evil' and 'radical Islam', Almond found it striking because "some of the most revered and oft-quoted figures in our Western political tradition have been capable of the most vicious acts of savagery – and yet all we ever hear about is how much the Middle East has to learn from us."

[444] Writing for The Guardian, Pankaj Mishra rejects the idea that the group is a resurgence of medieval Islam, saying instead: In actuality, ISIS is the canniest of all traders in the flourishing international economy of disaffection: the most resourceful among all those who offer the security of collective identity to isolated and fearful individuals.

[445]On 28 January 2017, then U.S. President Donald Trump issued a National Security Presidential Memorandum which called for a comprehensive plan to destroy ISIL to be formulated by the Defense Department within 30 days.

[113] According to scholar Fawaz Gerges writing in ISIS: A History, some "30 percent of the senior figures" in IS's military command were former army and police officers from the disbanded Iraqi security forces, turned towards Sunni Islamism and drawn to IS by the US de-Ba'athification policy following the US invasion of Iraq.

The Arab League, European Union, NATO, and GCC are part of the Counter-ISIL Coalition:[452] According to the Pentagon, by December 2017 over 80,000 ISIL fighters had been killed in Iraq and Syria by CJTF-OIR airstrikes.

[456] On 21 December 2019, over 33 Islamist militants were killed in Mali by French forces using attack helicopters, drones and ground troops, alongside the border with Mauritania where an Al-Qaeda-linked group operates.

[494] The Islamic State has been widely accused of committing war crimes, crimes against humanity, and of human rights abuses,[495][496][497] including systematic rape and other forms of sexual violence against both males and females,[498][499] mass killing of prisoners of war,[500] summary executions including the Camp Speicher massacre, public floggings, beheadings, politically motivated assassinations of judges; public officials; members of the security forces and others, and terrorizing residents of Derna, Libya among others.

[503] Sarah Leah Watson, Director of HRW Middle East and North Africa, said: "Commanders should understand that they may face domestic or international prosecution for the grave rights abuses their forces are committing.

"[504] The United Nations Commission on Human Rights has stated that the group "seeks to subjugate civilians under its control and dominate every aspect of their lives through terror, indoctrination, and the provision of services to those who obey".