Can a Muslim state declare war against another Muslim state?

Can a Muslim state declare war against another Muslim state?

Dear Brother / Sister,

A Muslim state cannot declare war against another Muslim state; a brother cannot shoot his brother.It is valid for both individuals and states. The Messenger of Allah prohibited a Muslim from pointing a weapon at his brother, let alone shooting him. He said,

“One of you cannot point his weapon at his Muslim brother.” 

Disagreements should be settled through negotiations. If a disagreement cannot be settled through dual negotiations, a committee of arbitrators is chosen. The parties have to accept the decree given by the arbitrators. If a party does not accept it, they become responsible for the war to break out. What is important here is that the committee of arbitrators must be really impartial and support the truth. 

Our Lord states the following in the Quran regarding the issue:

“If two parties among the Believers fall into a quarrel, make ye peace between them: but if one of them transgresses beyond bounds against the other, then fight ye (all) against the one that transgresses until it complies with the command of Allah; but if it complies, then make peace between them with justice, and be fair: for Allah loves those who are fair (and just).”(al-Hujurat, 49/9)

If a Muslim state attacks another Muslim state, acts cruelly and sheds blood, a defense war can be inevitable. In that case, the attacking party becomes responsible. The duty of the Muslims is to support the innocent people.

Questions on Islam