Inna allatheena amanoo wahajaroo wajahadoo bi-amwalihim waanfusihim fee sabeeli Allahi wallatheena awaw (surah Anfal: 72)

Tafseer Tafheem-ul-Quran by Syed Abu-al-A'la Maududi

(8:72) Surely those who believed and migrated and strove hard in the way of Allah with their possessions and their lives, and those that sheltered and helped them - they alone are the true allies of one another. And those who believed but did not migrate (to Dar-al-Islam), you are under no obligation of alliance unless they migrate. *50 And should they seek help from you in the matter of religion, it is incumbent on you to provide help unless it be against a people with whom you have a pact. *51 Allah is cognizant of all that you do.

Innal lazeena aamanoo wa haajaroo wa jaahadoo bi amwaalihim wa anfusihim fee sabeelil laahi wallazeena aawaw wa nasarooo ulaaa`ika ba`duhum awliyaaa`u ba`d; wallazeena aamanoo wa lam yuhaajiroo maa lakum minw walaayatihim min shai`in hatta yuhaajiroo; wa inistan sarookum fid deeni fa`alaiku munnasru illaa `alaa qawmim bainakum wa bainahum meesaaq; wallaahu bimaa ta`maloona Baseer

*50). The above verse is an important provision in Islamic constitutional law. For it prescribes that any agreement on guardianship would be applicable exclusively to Muslims who are either the original inhabitants of the territory which has become Dar al-Islam (the Domain of Islam) or Muslims who have migrated to the Dar al-Islam. As to Muslims living outside the jurisdiction of the Islamic state, the bond of religious brotherhood would doubtlessly exist between them and Muslim residents of the Islamic state. The two groups, however, would not have the relationship of walayah (mutual alliance). Likewise, a walayah relationship would not exist between Muslims who do not migrate to Dar al-Islam but come to it as Muslim subjects of a non-Muslim state.
The Arabic word walayah denotes the relationship of kinship, support, succour, protection, friendship, and guardianship. In the context of the present verse the word signifies the relationship of mutual support between the Islamic state and its citizens, and between the citizens themselves. Thus, this verse lays down that in a political and constitutional sense, only those Muslims who live within the territorial boundaries of the Islamic state will enjoy the privileges of walayah (guardianship) of the Islamic state. As for Muslims who are settled in a non-Islamic state, they are excluded from its political and constitutional guardianship.
It is difficult to spell out in detail the implications of this rule. Just to give some idea of it. it should be pointed out that because they lack guardianship the Muslims of Dar al-Kufr (the Domain of Unbelief) cannot inherit the property of a deceased Muslim in the Islamic state. Nor may they act as guardians of Muslim citizens of an Islamic state. Nor is it lawful for a matrimonial contract to be made between Muslims, one of whom is living in an Islamic state and the other outside of it. Likewise, the Islamic state may not appoint to an office of authority those who have not surrendered their citizenship of the non-Islamic state. Above all, these provisions of Islamic law determine the foreign policy of the Islamic state. (Cf. Ibn Qudimah, al-Mughni, vol. 8, pp. 456-8 - Ed.) Since this clause restricts the role and control of the Islamic state over Muslims living within that state, the Islamic state is not obliged to look after the Muslims outside its domain. The following tradition embodies this point: 'I am acquit of every Muslim living among the polytheists.' (Abu Da'ud. 'Jihad', 'Bab al-Nahy'an, 'katl man i'tasama bi al-Sujud - Ed.) Islamic law, therefore, strikes at the root cause of the conflict which bedevils the relationship between different nations. For, whenever a state tries to champion the cause of the minority living outside its territory, it gives rise to intricate problems which cannot be resolved even by a succession of wars.
*51). The above verse makes it clear that the Muslims living outside the Islamic state have no political bond with the Islamic state. This verse, however, does emphasize that those Muslims are not free of the bond of religious brotherhood. If Muslims living in a non-Islamic state are persecuted and seek help from the Islamic state or its citizens, it is incumbent upon the latter to help the persecuted Muslims.
While helping one's brethren-in-faith the Muslims are expected to act scrupulously. This help should be rendered without iritermitional oblioations and with due regard to the requirements of rnoral propriety.
If the Islamic state happens to be bound in a treaty relationship with a nation which inflicts wrong on Muslims, the oppressed Muslims will not be helped in a manner which is inconsistent with the moral obligations incumbent on the Islamic state as a result of that treaty .
The Qur'an uses the word mithaq for treaty. This expression is a derivative of an Arahic word which stands for trust and confidence. The expression, therefore, implies that the two parties trust each other, that there is no difference between-them irrespective of whether a no-war agreement has been formally, concluded or not.
The actual words of the verse "bainakum wa bainahum mithaq" ('[unless there be] a pact between you and them') make it plain that the treaty concluded by the Islamic state with a non-Muslim state does not merely bind the two governments. The moral obligations arising from that treaty are binding upon the Muslim nation as a whole including its individuals not to violate the obligations of the treaty into which an Islamic state has entered with some other state. However, it is only the Muslims of the Islamic state who are bound by the agreement signed by the Islamic state. Muslims living outside the Islamic state have no such obligations. This accounts for the fact that Abu Basir and Abu Jandal were not bound by the Hudaybiyah treaty concluded between the Prophet (peace he on him) and the Makkan unbelievers.