In "Some Answered Questions", 'Abdu'l-Baha explains the justification of Muhammad's military expeditions:
MUHAMMAD
Now we come to Muhammad. Americans and Europeans have heard a number of stories about the Prophet which they have thought to be true, although the narrators were either ignorant or antagonistic: most of them were clergy; others were ignorant Muslims who repeated unfounded traditions about Muhammad which they ignorantly believed to be to His praise.
Thus some benighted Muslims made His polygamy the pivot of their praises and held it to be a wonder, regarding it as a miracle; and European historians, for the most part, rely on the tales of these ignorant people.
For example, a foolish man said to a clergyman that the true proof of greatness is bravery and the shedding of blood, and that in one day on the field of battle a follower of Muhammad had cut off the heads of one hundred men! This misled the clergyman to infer that killing is considered the way to prove one's faith to Muhammad, while this is merely imaginary. The military expeditions of Muhammad, on the contrary, were always defensive actions: a proof of this is that during thirteen years, in Mecca, He and His followers endured the most violent persecutions. At this period they were the target for the arrows of hatred: some of His companions were killed and their property confiscated; others fled to foreign lands. Muhammad Himself, after the most extreme persecutions by the Qurayshites, who finally resolved to kill Him, fled to Medina in the middle of the night. Yet even then His enemies did not cease their persecutions, but pursued Him to Medina, and His disciples even to Abyssinia.
These Arab tribes were in the lowest depths of savagery and barbarism, and in comparison with them the savages of Africa and wild Indians of America were as advanced as a Plato. The savages of America do not bury their children alive as these Arabs did their daughters, glorying in it as being an honorable thing to do.[1] Thus many of the men would threaten their wives, saying, "If a daughter is born to you, I will kill you." Even down to the present time the Arabs dread having daughters. Further, a man was permitted to take a thousand women, and most husbands had more than ten wives in their household. When these tribes made war, the one which was victorious would take the women and children of the vanquished tribe captive and treat them as slaves.
[1 The Banu-Tamim, one of the most barbarous Arab tribes, practiced this odious custom.]
When a man who had ten wives died, the sons of these women rushed at each other's mothers; and if one of the sons threw his mantle over the head of his father's wife and cried out, "This woman is my lawful property," at once the unfortunate woman became his prisoner and slave. He could do whatever he wished with her. He could kill her, imprison her in a well, or beat, curse and torture her until death released her. According to the Arab habits and customs, he was her master. It is evident that malignity, jealousy, hatred and enmity must have existed between the wives and children of a household, and it is, therefore, needless to enlarge upon the subject. Again, consider what was the condition and life of these oppressed women! Moreover, the means by which these Arab tribes lived consisted in pillage and robbery, so that they were perpetually engaged in fighting and war, killing one another, plundering and devastating each other's property, and capturing women and children, whom they would sell to strangers. How often it happened that the daughters and sons of a prince, who spent their day in comfort and luxury, found themselves, when night fell, reduced to shame, poverty and captivity. Yesterday they were princes, today they are captives; yesterday they were great ladies, today they are slaves.
Muhammad received the Divine Revelation among these tribes, and after enduring thirteen years of persecution from them, He fled.[1] But this people did not cease to oppress; they united to exterminate Him and all His followers. It was under such circumstances that Muhammad was forced to take up arms. This is the truth: we are not bigoted and do not wish to defend Him, but we are just, and we say what is just. Look at it with justice. If Christ Himself had been placed in such circumstances among such tyrannical and barbarous tribes, and if for thirteen years He with His disciples had endured all these trials with patience, culminating in flight from His native land -- if in spite of this these lawless tribes continued to pursue Him, to slaughter the men, to pillage their property, and to capture their women and children -- what would have been Christ's conduct with regard to them? If this oppression had fallen only upon Himself, He would have forgiven them, and such an act of forgiveness would have been most praiseworthy; but if He had seen that these cruel and bloodthirsty murderers wished to kill, to pillage and to injure all these oppressed ones, and to take captive the women and children, it is certain that He would have protected them and would have resisted the tyrants. What objection, then, can be taken to Muhammad's action? Is it this, that He did not, with His followers, and their women and children, submit to these savage tribes? To free these tribes from their bloodthirstiness was the greatest kindness, and to coerce and restrain them was a true mercy. They were like a man holding in his hand a cup of poison, which, when about to drink, a friend breaks and thus saves him. If Christ had been placed in similar circumstances, it is certain that with a conquering power He would have delivered the men, women and children from the claws of these bloodthirsty wolves.
[1 To Medina.]
Muhammad never fought against the Christians; on the contrary, He treated them kindly and gave them perfect freedom. A community of Christian people lived at Najran and were under His care and protection. Muhammad said, "If anyone infringes their rights, I Myself will be his enemy, and in the presence of God I will bring a charge against him." In the edicts which He promulgated it is clearly stated that the lives, properties and honor of the Christians and Jews are under the protection of God; and that if a Muhammadan married a Christian woman, the husband must not prevent her from going to church, nor oblige her to veil herself; and that if she died, he must place her remains in the care of the Christian clergy. Should the Christians desire to build a church, Islam ought to help them. In case of war between Islam and her enemies, the Christians should be exempted from the obligation of fighting, unless they desired of their own free will to do so in defense of Islam, because they were under its protection. But as a compensation for this immunity, they should pay yearly a small sum of money. In short, there are seven detailed edicts on these subjects, some copies of which are still extant at Jerusalem. This is an established fact and is not dependent on my affirmation. The edict of the second Caliph [1] still exists in the custody of the orthodox Patriarch of Jerusalem, and of this there is no doubt.[2]
[1 Of Umar.]
[2 Cf. Jurji Zaydan's Umayyads and Abbasids, trans. D. S. Margoliouth.]
Nevertheless, after a certain time, and through the transgression of both the Muhammadans and the Christians, hatred and enmity arose between them. Beyond this fact, all the narrations of the Muslims, Christians and others are simply fabrications, which have their origin in fanaticism, or ignorance, or emanate from intense hostility.
(Abdu'l-Baha, Some Answered Questions, p. 18)
. I'm a 17 year old Baha'i living in the U.S. I read The Writtings every day (currently on the Book of Certitude and Selections from the writtings of Abdul Baha).
