When disunity is harmful for the Deen it is evil. If the disunity is beneficial for the Deen, it will not be evil notwithstanding it being harmful for the dunya. Hadhrat Ibraaheem (alayhis salaam)
had chosen a disunity about which the Qur’aan says:
“Verily, in Ibraaheem and those with him there is for you a beautiful character (code of life), when they said to their people: ‘We dissociate from you and from that which you worship besides
Allah. We reject you. Animosity and hatred have become manifest between us and you forever (and it will remain so) until you believe in Allah Alone.” (Qur’aan)

Can anyone condemn this disunity? Mentioning a reprehensible unity, Ibraaheem (alayhis salaam) said: “Verily, you have taken besides Allah idols as objects of mutual love among you in this worldly life. On the Day of Qiyaamah there will be mutual rejection among you. Some of you will curse others among yourselves, and for you will be the Fire.” (Qur’aan)
From this aayat it is quite clear that in opposition to Hadhrat Ibraaheem (alayhis salaam), the kuffaar had displayed a perfect unity. But this unity was never praiseworthy. In fact, Hadhrat Ibraaheem (alayhis salaam) had eradicated the very foundations of this unity. This unity was in opposition to the Haqq. Therefore, understand well that unity is the objective and desirable only when it is beneficial for the Deen., and disunity is abhorrent only if it is harmful forthe Deen.

If unity is detrimental for the Deen and disunity is beneficial for the Deen, then such disunity is the objective.