What is the ruling of Islamic law on Arab unity, given the presence of Arab Muslims, Christians, and Jews?

The Shari'ah commanded the rejection of blameworthy calls for 'asabiyyah (tribalism/ partisanship), such as nationalism and tribalism. The Prophet, peace and blessings be upon him, said: "Leave it, for it is rotten." What is required of a Muslim is to be partisan only to Islam. The blameworthy racial affiliation is that which is based on mutual support regardless of right or wrong. As for supporting one another in truth, there is no harm in it, as Shaykh al-Islam said: "What is prohibited in this regard is merely a man's absolute partisanship to his group, which is based on the principles of Jahiliyyah (pre-Islamic ignorance). As for supporting it in truth without deviation, it is good, obligatory, or praiseworthy."