George W Bush indirectly created ISIS.

ISIS founder Zarqawi's hatred for the Shia people and their strong cooperation with the U.S forces allowed Zarqawi to create the ISIL.

ISIS founder Zarqawi's hatred for the Shia people and their strong cooperation with the U.S forces allowed Zarqawi to create the ISIL. On September 11, 2001, the World Trade Center and the Pentagon were attacked by eight Saudi Nationals belonging to the radical Islamic group known as Al Qaeda headed by Osama Bin Laden, operating out of the Afghani mountains. Al Qaeda was backed by the Taliban, a Pashtun ethnic group led by Mullah Mohammad Omar. In retaliation for the twin towers' attack, U.S. President George W Bush launched a counteroffensive codenamed 'Operation Enduring Freedom,' most commonly known as the 'global war on terror.' This offensive operation by the United States and its allies began in October 2001.

The founder of the Islamic State or the ISIS (previously known as ISIL or the Islamic State of Iraq and the Levant), Abu Mus'ab al-Zarqawi, was a Jordanian National who fought the Russians in Afghanistan. He was imprisoned in Jordan in 1994, and upon his release in 1999, moved to Afghanistan and started an insurgent training camp in the Afghani city of Herat. Zarqawi did not give the oath of fealty to Bin Laden, and hence his outfit remained loosely tied to the Al Qaeda. After the U.S. invaded Afghanistan in October 2001, Zarqawi moved to Northern Iraq and set up an organization known as 'Jama‘at al-Tawhid wa’l-Jihad' (“the Group of God’s Unity and Jihad) in 2002. He strongly opposed the Shi'ites both in theological terms and politically.

After the U.S. forces invaded Iraq in 2003 and captured its leader Saddam Hussein on December 13, 2003, during an operation named 'Operation Red Dawn,' Baghdad's political balance was previously dominated by Sunnis, started to change. For the first time in Iraq's history, a Shia majority won its prime ministership, including many other top ministerial posts. Iraq also saw its first Kurdish president, Jalal Talabani taking office in 2005. These changes in the political balance in Iraq saw widespread sectarian violence in the country.

Zarqawi gave the oath of fealty to Osama Bin Laden in 2004. In one of his letters intercepted by the U.S forces, Zarqawi's hatred for the Shi'ite community was evident. He even feared that the Shi'ites would willingly cooperate with the Americans to seize power in Iraq. Taking advantage of the sectarian violence and the rising number of youths willing to participate in insurgent activities in the country, Zarqawi got himself involved in multiple bombings, kidnappings, and beheadings in Iraq, until he was killed in a U.S. airstrike in 2006. His organization later renamed itself ISIS in 2014.

After ISIS became a massive challenge to the U.S. forces in Iraq, in September 2014, the United States announced an international coalition to defeat ISIS. Many historians and middle east watch groups argue that Goerge W Bush's decision to invade Iraq in 2003 paved the way for political instability in the country, facilitating the ISIL or present-day Islamic State's rise. The founder of the Islamic State, Abu Mus'ab al-Zarqawi, saw the Shi'ites as a threat to Islam itself. He has once said to have told that Shi'ites were beyond the bounds of Islam. Zarqawi's hatred for the Shi'ites and their cooperation with George W Bush's United States together paved the way for the rise of one of the world's most brutal terror outfits presently known as the ISIS or Islamic State.