What are the limits of belonging to a specific country in Islam, and is it permissible to show fanaticism towards one's homeland, knowing that the basic principle is that we are all Muslims?

Allah commanded adherence to His rope and forbade division and disagreement, saying: "And hold firmly to the rope of Allah all together and do not become divided," and "And do not be like those who became divided and differed." Any gathering under a banner other than Islam, upon which loyalty and disavowal, love and hatred are based, is among what the Shari'ah has forbidden. The Muslim's loyalty must be to his religion, and his love and support to the people of his faith, without regard for nationalism or ethnicity. As for affiliation with a tribe, group, or nation for acquaintance and cooperation, not for boasting and quarreling, there is no objection to it. However, calling to a bond other than Islam, such as nationalisms and tribalisms, is a call to abandon Islam and reject the heavenly bond. The wisdom behind making people nations and tribes is for acquaintance, not fanaticism. The blameworthy affiliation to a country, people, or race is that which intends mutual support and assistance not based on truth and falsehood, but solely on nationalism or ethnicity. Thus, every call to blameworthy tribalism, whether national, tribal, or otherwise, is among the calls of Jahiliyyah (the pre-Islamic era of ignorance). The Prophet, peace and blessings be upon him, said: "Whoever calls to the calls of Jahiliyyah, then he is among the heaps of Hellfire."