This might be a question to many; why do Muslim women have to wear the hijab, and moreover, why do non-Muslims who live in Muslim countries (who enforce this Islamic ruling such as
A few points and principles need to be paid attention to in order to get the answer to your question:
1- What can be concluded from the Quran is that the hijab isn’t a limitation, it is security and preserves one's dignity.
2- Before it being an Islamic ruling, it was a gift to all religions and societies, because of all the important benefits it encompasses.
3- In order for all of this ruling's benefits to take place and the goals it has been legislated for to be fulfilled, all of those living in the Islamic society, regardless of them being Muslim or not, need to observe it, or else its purpose will be defeated.
4- All religious minorities have to abide by the laws of the countries they live in, and
5- In reality, followers of other religions also have to observe the hijab if they want to have truly followed their religion, because as was said, the hijab isn’t something that only belongs to Islam.
The Islamic hijab, which stems from the pure human nature and religious beliefs, brings safety, peace of mind, self respect, self esteem and the like for both men and women.
Truly, this Islamic ruling which has been wisely made obligatory upon Muslim women, is a divine gift for all human and Islamic societies.
The tendency of women in the West today to observe the hijab after years of experiencing the bad outcomes of not observing it corroborates the famous statement: "The hijab is security, not limitation".
Paying attention to its benefits and outcomes helps us better comprehend how it is a godly gift and that observing it should be made part of the law in all societies; Islamic or non-Islamic.
Its major benefits
In general, one can point to the following as its major benefits:
a) Peace of mind for the individual: One of its major personal benefits is that it prevents the arousal of others' lust. On the other hand, free interaction between men and women usually leads to such a matter, fanning its flames and making the sex drive even more intense and unyielding as it already is.
b) The stability of the family: Another important matter that factors into this ruling is that the hijab limits all sexual pleasures to legitimate ones inside the home, resulting in a stronger relationship between the husband and wife or mother and father of the family. When this relationship strengthens, so does the relationship between other members of the family. On the other hand, not observing hijab results in the opposite, shattering these relationships and sometimes destroying families, which are actually supposed to be the building blocks of society.
Concerning the impact of improper and inadequate covering on the wreckage of families, one writer says: "In a society in which proper covering isn’t observed, men and women are continuously comparing; comparing what they have with what they don’t, and what eradicates families are the desires that follow this comparison, especially the desires of men."
Clearly, the sinister fruits of these comparisons have grown much more in societies that are deprived of the blessing of hijab; one of those fruits being the eradication of families. This is what can be seen happening in the West today. Conversely, not only have societies in which the hijab has been accepted as a God-given blessing and is observed in, taken the first step in protecting the family, but they have also kept their dignity and saved themselves from the bother, harm and looks of others which like arrows, pierce the body of society and individuals.
c) Preparing the ground for spiritual growth and perfection: We believe that the hijab isn’t limitation; it is security. In an environment in which the hijab is observed, there is a higher potential for growth and perfection, and in other words, people better get a better chance to do so. Therefore, we consider not observing the hijab a deadly poison that blocks man's movement towards the true goal he was created for. The more it isn’t observed, the more he strays from that goal.
As with other Islamic rulings, this ruling has been divinely legislated for the purpose of preparing the ground for man's quest for perfection. It is because of this that the woman has been compared to the flower; she has to cover and protect herself from plunderers who want to "pick" her.
The woman has been known as a precious pearl which has to be kept safe in the "jewelry box" of hijab, in order to be safe from all outsiders.
Women must appear in the public and in places where non-mahrams are present with the proper dress code, so that others can live their lives striving for spiritual perfection at ease and with peace of mind.
Of course there are many other great benefits the hijab entails, which all can't be listed in this short article.
All of the above being said, now we can conclude that: The ruling of hijab is an Islamic one with reasons that back it, and needs to be observed by both Muslims and non-Muslims who live in the Islamic society.
It is because of these reasons that Allah (swt) says in verse 31 of surah Nur: : "وَ قُل لِّلْمُؤْمِنَتِ یَغْضضنَ مِنْ أَبْصرِهِنَّ وَ یحْفَظنَ فُرُوجَهُنَّ وَ لا یُبْدِینَ زِینَتَهُنَّ إِلا مَا ظهَرَ مِنْهَا وَ لْیَضرِبْنَ بخُمُرِهِنَّ عَلى جُیُوبهِنَّ وَ لا یُبْدِینَ زِینَتَهُنَّ إِلا لِبُعُولَتِهِنَّ أَوْ ءَابَائهِنَّ أَوْ ءَابَاءِ بُعُولَتِهِنَّ أَوْ أَبْنَائهِنَّ أَوْ أَبْنَاءِ بُعُولَتِهِنَّ أَوْ إِخْوَنِهِنَّ أَوْ بَنى إِخْوَنِهِنَّ أَوْ بَنى أَخَوَتِهِنَّ أَوْ نِسائهِنَّ أَوْ مَا مَلَکَت أَیْمَنُهُنَّ أَوِ التَّبِعِینَ غَیرِ أُولى الارْبَةِ مِنَ الرِّجَالِ أَوِ الطفْلِ الَّذِینَ لَمْ یَظهَرُوا عَلى عَوْرَتِ النِّساءِ وَ لا یَضرِبْنَ بِأَرْجُلِهِنَّ لِیُعْلَمَ مَا یخْفِینَ مِن زِینَتِهِنَّ وَ تُوبُوا إِلى اللَّهِ جَمِیعاً أَیُّهَ الْمُؤْمِنُونَ لَعَلَّکمْ تُفْلِحُونَ" (And tell the faithful women to cast down their looks and to guard their private parts and not to display their charms, except for what is outward [their hands and faces] and they must draw their scarfs over their bossoms, and not display their charms except to their husbands or their fathers, or their husbands' fathers, or their sons, or their husbands' sons, or their brothers, or their brothers' sons, or their sisters' sons, or their women, or their slave girls, or male dependants lacking [sexual desire], or children uninitiated to womens' parts, and let them not thump their feet to make known their hidden ornaments. Rally to Allah in repentance, O faithful, so that you may be felicitous.). In the end of the verse, all acts that might lead to the sexual arousal of men have been prohibited; it says that the faithful women shouldn’t thump their feet so that others hear the sound of their anklets! This shows that regarding matters that have to do with modesty and chastity, Islam is very strict, to the extent that it doesn’t even allow such actions that might lead to problems. It can easily be concluded from this verse that anything that might possibly arouse the lust of others, such as spreading inappropriate images, videos, stories and the like are all forbidden. Without a doubt, the Islamic society should be free of all of the things that lead those who see them to corrupt places and result in the corruption and perversion of young girls and boys.
Clearly, in order for all of the good outcomes of the hijab to take place, the cooperation and observance of all individuals in the Islamic society is needed; Muslim or non-Muslim, and it doesn’t make sense to say that not observing the hijab on behalf of non-Muslims in a Muslim society has no bad outcomes and will not entail any of the bad results that were mentioned above.
This question is like asking why non-Muslims living in a Muslim society can't openly drink alcohol. The answer to such a question would be that Islam limits personal freedom when it comes to the benefit of society in its entirety. We believe that sinning in public is also a separate sin by itself. For example, breaking the fast in the holy month of Ramadhan is a sin, while publicizing it is another. The reason for such is that there are many bad effects the publicity of such a sin has that make it a separate sin. Essentially, this is the same reason why enjoining good and forbidding evil is mandatory; because it helps preserve and keep society healthy from all impurities.
Imagine yourself not knowing how to swim and sitting in a boat next to others in the middle of the lake. All of a sudden, one of the passengers wants to make a hole in it. In such a situation, will you just sit there and say that he is a free man and can do anything he likes?! Of course not! You will stop him. The same goes with society; unless you don't believe that society is like the boat that needs to be protected and escorted to shore safely, which calls for a separate discussion on the subject because of the premises of the argument on it.
Verse 110 of surah Ale-Imran says: "You are the best nation [ever] brought forth for mankind: you bid what is right and forbid what is wrong, and have faith in Allah…", introducing the enjoining of good and forbidding of evil as a general law that is one of the traits of the Muslim society. In verse 104 of the same surah, the quran says: "There has to be a group among you summoning to the good, bidding what is right, and forbidding what is wrong. It is they who are the felicitous." which shows that there also has to be a certain group of people in the Islamic society that are responsible for this act; that group being the government and those working in it.
Of course, this doesn’t mean that this obligation can't be found in other religions, because verses 113 and 114 of surah Ale-Imran tell us that the People of the Book who embraced Islam had three characteristics; belief in the hereafter, enjoining good and forbidding evil and being front-runners in doing good deeds.
So the Islamic government and its leaders are responsible for the training and growth of the Islamic society's youth and legally and Islamically aren’t allowed to compromise or take anything that leads society to corruption lightly and have to exhaust everything needed to pave the way for the peace of mind and perfection of society.
Also, according to Quranic verses and Islamic tradition, just as much as the safety and protection of religious minorities who have contracted the Dhimmah contract with the Islamic government are the Islamic government's responsibility, observing Islamic boundaries in an Islamic society by the Islamic government is also its responsibility. The Islamic leader has in no way any right to accept any terms of a contract with the non-Muslims that is in conflict with Islamic law. The author of the famous fiqh book, Jawahirul-Kalam, says: "Religious minorities cannot change the customs that an Islamic society has, and according to their contract with the Islamic government, they must observe Islamic boundaries and laws.
Also, taking a look at the hijab's past tells us that the hijab is one of the oldest customs of human civilization and that it has been observed in religions such as Zoroastrianism, Christianity and Judaism and that it was stricter than Islam in Judaism. Therefore, if they actually want to truly practice their religions, they will have to do the same!
In the end we would like to ask those who criticize the enforcement of hijab regarding minorities how they rationalize some of the laws legislated against minorities (particularly Muslims) in western countries who claim are the role models and leaders in democracy and freedom; laws that for instance prevent women from being in certain places which they are legally entitled to, while they themselves say that dressing Islamically in no way contradicts others’ freedom and is something totally personal.
For further reading:
1- Morteza Motahhari, Falsafeye Hejab
2- Mahdi Eshtehardi, Hejab Bayangare Shakhsiyyate Zan
3- Jafar Sheikhul-Eslami, Farhange Hejab
4- Mohammad Mahdi Taj Langaroodi, Pasdarane Hejab
 GholamAli Haddad Adel, Farhange Berehnegi va Berehnegiye Farhangi, pg. 69-70.
 Makarem Shirazi, Tafsir Nemouneh, vol.14, pg.455.
 Makarem Shirazi, Payame Quran, vol.10, pg.254 and 256.
 Ibid, pg.257.
 For further information, see: AbbasAli Amid Zanjani, Huquqe Aqalliyyatha.
 Muhammad Hasan Najafi, Jawahirul-Kalam, vol.21, kitabul-jihad, pp.268-269.
 For further information, see: Ali Muhammad Ashnaee, Hijab dar Adyane Elahi; Shahid Mutahhari, Mas’aleye Hejab.