With regard to the issue of whether a land is categorized as Dar al-Islam or Dar al-Harb, there are two main views among scholars.
The first view is that a land becomes Dar al-Islam when the laws of Islam are implemented therein; the second view is that any land in which the Muslims are safe to practice their religion, then it is included in the category of Dar al-Islam.
Within the first view, there are two opinions; the first opinion is that the implementation of the laws of Islam must be at the governmental level, and the second opinion is that implementation needs to only be at the popular level. That is to say, if the people themselves, regardless of the laws of the state, practice Islam and implement its rules, then that is a land within Dar al-Islam.
Ibn Taymiyyah said about method of categorization, “It is a temporal attribution depending on its inhabitants. Every land that is inhabited by the pious believers is the land of the devoted servants of Allah at that time. Every land inhabited by the disbelievers is a land of kufr at that time. Every land inhabited by the evildoers is a land of immorality at that time. If the inhabitants change what we mentioned or if others change it, it becomes their land”.
The strongest view is that these two aspects must be combined; law at the governmental level, and implementation on the popular level. However, we must not be extreme in the issue of law at the governmental level. The presence of all the laws of Islam are not required to categorize a land as being from Dar al-Islam; if that were the case, there would have been no land since the abdication of Hassan bin Ali that qualified as being Dar al-Islam. No, the laws which determine the categorization of a land are of different importance; the most important of them being the Salah.
Therefore, if one does not hear the call to prayer in a land and does not find mosques therein, this is evidence that that land is the land of kufr. If one hears the call to prayer and finds mosques, even if some of the manifestations of the law are missing, the land is still a land of Islam. Anas ibn Maalik said, “The Messenger of Allah (peace and blessings of Allah be upon him) would attack at dawn. He would listen for the call to prayer. If he heard the call to prayer, he would refrain from attacking. Otherwise, he would attack.”
An-Nawawi and others explained that this hadith clarifies that the presence of the adhan is itself sufficient to determine whether a land is from Dar al-Islam or not. The adhan, the existence of masaajid, etc, indicate both governmental and popular implementation of the most important manifestations of Islam; whatever shortcomings there may otherwise be in the land, it is from the oppression of the ruler or the sin of the people, but this oppression or sin does not negate the classification of the land as being from Dar al-Islam