Therefore, when ye meet the Unbelievers (in fight), smite at their necks; At length, when ye have thoroughly subdued them, bind a bond firmly (on them): thereafter (is the time for) either generosity or ransom: Until the war lays down its burdens. Thus (are ye commanded): but if it had been Allah's Will, He could certainly have exacted retribution from them (Himself); but (He lets you fight) in order to test you, some with others. But those who are slain in the Way of Allah,- He will never let their deeds be lost.
Now I know you will come back with " This is only for war time " etc., but Islam is at permanent war with non-Muslims, until they say there is no god but Allah and Muhammad is his Prophet. Dar-ul-harb has to be converted to Dar-ul-Islam.
Note also, that the war is to be waged with others for no reason other than the unbelief of the infidels. A clear mandate for religious war!