Muslims and non-Muslims have different values. A non-Muslim may build his life on some values such as human rights, freedom, democracy, peace, etc. However, Islam teaches us to live in accordance with that we are mortal, we came here for a reason, we will be asked about each of our actions after death.
Humans can forget and slip easily. We can forget that we are living on earth which is created by Allah and that everything we eat, drink, benefit belongs to Allah. So, in order not to forget Allah, we pray at least five times in a day.
With five prayers in a day, we also practice our full lifespan, our birth and death. Fajr is like our birth from a dark place to this world. Dhuhr is like our youth... And Isha is like our death and being embedded under a dark and silent ground. It is like living each part of our lives remembering Allah.
We also gather together at a specific place on a specific time to practice our Hajj. It is like training for resurrection day. In a simple dress and inside a huge crowd with people from different nations far from wordly thoughts. We also learn and train with fasting and zakat that we aren't the actual owner of what we have.
For a careful Muslim, rain, storm, animals, trees also can remind Allah. Rain teaches mercy of Allah, storm teaches magnificence of Allah. However, beauty of women will instantly kill your contemplation. It is not necessary to lead men to lust. You will forget Allah and start being secular.
Thinking on this basis, hijab helps Muslims living as good servants of Allah. Muslims obey Allah, cover their bodies as Allah ordered them, and lower their gazes. However, a foreign woman without hijab can easily break the system. Muslim men will be distracted to look, Muslim women will be distracted show their own beauty. So, it is very natural for a Muslim country to force foreign women to wear hijab.
However, non-Muslim countries can allow wearing hijab because they claim freedom and human rights. Is Islam against freedom and human rights? Actually, the words are tricky. A Muslim man can't look at everything. A Muslim can't eat during fast and can't eat meat slaughtered without mentioning name of Allah. Then, it is important what is meant by freedom and human rights.
At this point, someone may ask that do Muslims always remember Allah? Is it only the women beauty that will hinder thinking about Allah? I can say no. We are covering rain, storm, animals, trees whatever may remind Allah. We put advertisement and entertainment tools everywhere inviting to the world. We are running from meeting to meeting. Coming home at night and watch TV. We love world, don't want to think about death and hardly find time for prayers. I want to mention a hadith here:
Thawban, radi Allahu anhu (may Allah be pleased with him), one of the
companions of the Prophet (saws) and a freed slave, narrated a hadith
(prophetic saying) of the beloved Prophet (saws). He related that the
Messenger of Allah (saws) said, “The nations are about to call each
other and set upon you, just as diners set upon food.”
It was asked, “Will it be because of our small number that day?”
The Prophet (saws) answered, “Rather, on that day you will be many,
but you will be like foam, like the foam on the ocean. And Allah will
remove the fear of you from the hearts of your enemies and will throw
wahn (weakness) into your hearts.”
Someone then asked, “O Messenger of Allah! What is Wahn?”
He replied, “Love of the world and the hatred for death” (Abu Dawood
4297).
Muslims are glad to wear hijab in non-Muslim countries but those countries doesn't have to allow. You can't be sure what will happen tomorrow. Human rights doesn't always work.