Pan-Islamism and Pan-Arabism were both movements born out of anti-colonialism and opposed western political involvement, but they are not the same and have different history. There is no monolith in the middle east. Neither a Muslim nor an Arab Monolith. If you think all Muslims or all Arab people think the same you’re just being racist.
Hamas, while associated with the Muslim Brotherhood in the past, is not the same as the Muslim Brotherhood.
When Israel occupied the Palestinian territories in 1967, the Muslim Brotherhood members there did not take active part in the resistance, preferring to focus on social-religious reform and on restoring Islamic values. This outlook changed in the early 1980s, and Islamic organizations became more involved in Palestinian politics. The driving force behind this transformation was Sheikh Ahmed Yassin, a Palestinian refugee from Al-Jura. Of humble origins and quadriplegic, he became one of the Muslim Brotherhood’s leaders in Gaza. His charisma and conviction brought him a loyal group of followers, upon whom he depended for everything from feeding him and transporting him to and from events to communicating his strategy to the public. In 1973, Yassin founded the social-religious charity Mujama al-Islamiya (“Islamic center”) in Gaza as an offshoot of the Muslim Brotherhood.
The idea of Hamas began to take form on December 10, 1987, when several members of the Brotherhood convened the day after an incident in which an Israeli army truck crashed into a car at a Gaza checkpoint, killing four Palestinian day-workers, the impetus of the First Intifada. The group met at Yassin’s house to strategize on how to maximize the incident’s impact in spreading nationalist sentiments and sparking public demonstrations. A leaflet issued on December 14 calling for resistance is considered its first public intervention, though the name Hamas itself was not used until January 1988
To many Palestinians, Hamas represented a more authentic engagement with their national aspirations. This perception arose because Hamas offered an Islamic interpretation of the original goals of the secular PLO, focusing on armed struggle to liberate all of Palestine. This approach contrasted with the PLO’s eventual acceptance of territorial compromise, which involved settling for a smaller portion of Mandatory Palestine. Hamas’s formal establishment came a month after the PLO and other intifada leaders issued a 14-point declaration in January 1988 advocating for the coexistence of a Palestinian state alongside Israel.