I would like to clear some misconceptions which many muslims commonly utter in regard to the actions of the Mujahideen brothers and sisters. When you say civilians, I suppose you mean those people from the land of the enemies who do not fight with guns against the muslims. Regardless whether they directly fight or not, if their governments are fighting Islam and muslims, then their people become a legitimate targets of muslims. This is a Islamic ruling. Please read the Tafsir of Verses 2:190-2:193 (Tafsir Ibn Kathir) at
http://tafsir.com/default.asp?sid=2&tid=4985
The Command to fight Those Who fight Muslims and killing Them wherever They are found:
2:190. And fight in the way of Allah those who fight you, but transgress not the limits. Truly, Allah likes not the transgressors.) (2:191. And kill them wherever you find them, and turn them out from where they have turned you out. And Al-Fitnah is worse than killing. And fight not with them at Al-Masjid Al-Haram (the sanctuary at Makkah), unless they (first) fight you there. But if they attack you, then kill them. Such is the recompense of the disbelievers. ) (2:192. But if they cease, then Allah is Oft-Forgiving, Most Merciful.) (2:193. And fight them until there is no more Fitnah (disbelief and worshipping of others along with Allah) and the religion (all and every kind of worship) is for Allah (Alone). But if they cease, let there be no transgression except against Az-Zalimin (the polytheists and wrongdoers).)
Abu Ja`far Ar-Razi said that Ar-Rabi` bin Anas said that Abu Al-`Aliyah commented on what Allah said:
(And fight in the way of Allah those who fight you,)
Abu Al-`Aliyah said, "This was the first Ayah about fighting that was revealed in Al-Madinah. Ever since it was revealed, Allah's Messenger used to fight only those who fought him and avoid non-combatants. Later, Surat Bara'ah (chapter 9 in the Qur'an) was revealed.'' `Abdur-Rahman bin Zayd bin Aslam said similarly, then he said that this was later abrogated by the Ayah:
(then kill them wherever you find them) (9:5).
However, this statement is not plausible, because Allah's statement:
(...those who fight you) applies only to fighting the enemies who are engaged in fighting Islam and its people. So the Ayah means, `Fight those who fight you', just as Allah said (in another Ayah):
(...and fight against the Mushrikin collectively as they fight against you collectively.) (9:36)
This is why Allah said later in the Ayah:
(And kill them wherever you find them, and turn them out from where they have turned you out.) meaning, `Your energy should be spent on fighting them, just as their energy is spent on fighting you, and on expelling them from the areas from which they have expelled you, as a law of equality in punishment.'
"Please know >...equality in punishment< this important issue. Their people can be killed as Sheik Osama Bin Laden explained in his following letter to the American people. I have quoted the relevant part of the letter:"
Full text: bin Laden's 'letter to America'
http://www.informationclearinghouse.inf ... le6537.htm
(3) You may then dispute that all the above does not justify aggression against civilians, for crimes they did not commit and offenses in which they did not partake:
(a) This argument contradicts your continuous repetition that America is the land of freedom, and its leaders in this world. Therefore, the American people are the ones who choose their government by way of their own free will; a choice which stems from their agreement to its policies. Thus the American people have chosen, consented to, and affirmed their support for the Israeli oppression of the Palestinians, the occupation and usurpation of their land, and its continuous killing, torture, punishment and expulsion of the Palestinians. The American people have the ability and choice to refuse the policies of their Government and even to change it if they want.
(b) The American people are the ones who pay the taxes which fund the planes that bomb us in Afghanistan, the tanks that strike and destroy our homes in Palestine, the armies which occupy our lands in the Arabian Gulf, and the fleets which ensure the blockade of Iraq. These tax dollars are given to Israel for it to continue to attack us and penetrate our lands. So the American people are the ones who fund the attacks against us, and they are the ones who oversee the expenditure of these monies in the way they wish, through their elected candidates.
(c) Also the American army is part of the American people. It is this very same people who are shamelessly helping the Jews fight against us.
(d) The American people are the ones who employ both their men and their women in the American Forces which attack us.
(e) This is why the American people cannot be not innocent of all the crimes committed by the Americans and Jews against us.
(f) Allah, the Almighty, legislated the permission and the option to take revenge. Thus, if we are attacked, then we have the right to attack back. Whoever has destroyed our villages and towns, then we have the right to destroy their villages and towns. Whoever has stolen our wealth, then we have the right to destroy their economy. And whoever has killed our civilians, then we have the right to kill theirs.
There are verses in the Holy Quran which talks about revenge and retaliation. Here are some of them.
005 - Al-Maidah 45. And We ordained therein for them: "Life for life, eye for eye, nose for nose, ear for ear, tooth for tooth, and wounds equal for equal." But if anyone remits the retaliation by way of charity, it shall be for him an expiation. And whosoever does not judge by that which Allah has revealed, such are the Zalimun (polytheists and wrongdoers - of a lesser degree).
42:39. And those who, when an oppressive wrong is done to them, they take revenge.
42:40. The recompense for an evil is an evil like thereof, but whoever forgives and makes reconciliation, his reward is due from Allâh. Verily, He likes not the Zâlimûn (oppressors, polytheists, and wrong-doers, etc.).
42:41. And indeed whosoever takes revenge after he has suffered wrong, for such there is no way (of blame) against them.
42:42. The way (of blame) is only against those who oppress men and wrongly rebel in the earth, for such there will be a painful torment.