There is a profound misunderstanding about the term Islam. It is often by its members and outsiders likewise considered to be a religion. While there is no doubt that religion is part of it, it is not its primary feature. The current conflict between Islam and other cultures is not based on different beliefs, but on cultural characteristics, which have no religious justification and can neither be found in the holy scripture of Islam, the so called "quran", nor in the biographic anecdotes of its founder Mohammed, the so called "ahadith".
There is no "divine commandment" to grow a beard, to wear Arab-style clothes, to cover women in black coats, to speak Arabic or whatever else distinguishes the typical muslim from other human beings. Why would muslims pray towards Saudi Arabia knowing that their god doesn't actually live there, but is supposed to be omnipresent? All these characteristics of Islam are simply not of a religious nature.
Some quote the rejection of the divinity of Jesus and the concept of trinity as a proof of Islam being distinct from Christianity. But christian beliefs are not homogeneous. Many christians like Jehovah's Witnesses also reject these concepts. Muslims have far more in common with Catholicism than many other christian sects like the Church of the Latter Day Saints have with Catholicism.
Muslims are christians. They are just one branch of it like Catholicism, Eastern Orthodoxy, Jehova's Witnesses, Nestorianism etc. Mohammed did not found a new religion, he brought Arian Christianity to Arabia. He was for Arabia, what was Saint Patrick was for Britain. Since he was illiterate he could not bring the original christian bible with him but had to retell episodes from it as he remembered them, which were later compiled into the "quran". Essentially the quran is a collection of bible comments. The book itself has no chronological structure and remains incomprehensible, if the reader has not read the bible before. Without knowledge of the bible stories, a reader of the quran would have no idea what its statements refer to. There is nothing new revealed in the quran, which could not already be found in the bible with small inaccuracies about details, where Mohammed's memory apparently failed (e.g. confusion of Ismael with Isaac).
However the conflict between Islam and the christian world is not about those religious details, it is about culture. It is about the role of women in society, about behavior code and laws, in short about the so called "shariah", the islamic code of laws. And laws are not a matter of religion, they are a matter of politics. Therefore the conflict between Islam and the rest of the world is a political one, not a religious one.
Many particularities of Islam like the pilgrimage to Mecca or the Arabic name "al-Lah" for their god were the result of a political compromise between Mohammed and Abu Sufyan, the leader of the Quraysh tribe that ruled Mecca in order to negotiate the surrender of the city. The Quraysh did not want to lose their income through pilgrims that visited the pagan shrine kaaba. So the Quraysh gave up all other gods apart from their supreme god al-Lah and forced Mohammed to include the kaaba into his state religion.
If Islam is no religion, so what is it?
Islam is definitely a culture. it is the Arab culture to be precise. The term "Islam" means submission and it refers to the submission under the rule of the Arab conquerors who submitted the entire Middle East in the 7th century. "Muslim" can be translated as "one who submits", and it means he submits to the Arab rule. Neither "Islam", nor "muslim" are religious terms. Arabs call their religion "deen" Deen is sometimes wrongly translated as meaning any religion in general. But the term deen does not include Buddhism, Hinduism or Paganism. They are called "shirk", not "deen". Deen only refers to the religion of Mohammed. And this includes Christians and Jews, which are together with the muslims called "People of the Book". "Book" hereby refers to the bible, not to the quran. So Mohammed and his contemporaries were quite aware that they were part of the one christian religion. There is even a hadith (anedote from the life of Mohammed), where the pagan temple guard Sulami refers to the advancing muslim army as "christians" [Ishaq, 565]. Islam was only meant to be a political term referring to the subjugated peoples. When Mohammed's contemporaries referred to their religion, they called it "deen", when they referred to the political dominion of the Arab tribes they called it Islam.
Islam is Arab culture imperialism. It is the way how Arabs spread their hegemonic power over the world. The goal is submission to Arab supremacy. Muslims have to speak Arabic, to adopt Arab clothes, Arab customs.and Arab laws. They have to show reference to the homeland of Arabia during daily prayers and pay tribute to the principal shrine of the Arabs during a pilgrimage. It is not a matter of faith, it is a matter of loyalty to Arabia.
You become a muslim by swearing a loyalty oath to Mohammed, the first leader of the Arabs who united their tribes. This loyalty oath is called "shahadah". It is not sufficient to believe in al-Lah, who is considered to be the same as the christian and Jewish god. This only gives you the inferior "dhimmi" status, which means having to pay tribute to the Arab overlords and not being allowed to bear arms. Being a muslim is only a matter of loyalty. The faith does not count. If you don't swear the loyalty oath to the first Arab leader, you cannot be trusted in the eyes of the Arab imperialists.
Different Concepts of States
The Western world makes a huge mistake when categorizing Islam as a religion. It is something quite different. Its nature is political. It is not a religion, it is a nationality.
To understand the concept of muslim as nationality, we have to look at the history of our modern concept of a state. If we say "state" we mean a nation state. This is a concept that has come up with the "Westphalian System" in the 17th century after the 30-Years-War. A state became a territorial unit that included all human beings within its border. People were subject to the laws of the territory where they were. They became members of the state by birth in its territory (ius solis) or by being the off-spring of somebody born in its territory (ius sanguinis). The nation state is limited by its territory. It is a territorial state. A person travelling into the territory of another state doesn't take his laws with him. He becomes subject to the laws of the state in whose territory he is.
Before this concept of a nation state, there was a different concept of state, the "nation of personal loyalties" (German: Personenverbandsstaat). It is typical for tribal or feudal communities. A person belongs to a tribe or to his feudal lord, no matter in which territory his tribe moves. This kind of state does not include a particular territory, it includes people. As a member of this state, you remain always a subject of its laws, no matter where you go.
This is the concept of state that Islam as a nation is based on. A muslim is subject to islamic shariah law, no matter where he goes and in which nation state's territory he resides. Belonging to Islam as a nation supersedes all modern (Westphalian) concepts of nationality.
It needs to be understood that the nationality of a muslim cannot be French, American, Egyptian, Lebanese or whatever. His nationality is muslim. A muslim cannot have any other nationality, and he will only obey to the laws of his nation, the nation of Islam. The concept of "nations of personal loyalties" was common in the time when Islam as a nation was born. And Islam has not adjusted its understanding according to the Westphalian System. Islam remains a Personenverbandsstaat.
If we understand this, we will understand why muslims behave as they do, why apostasy is considered treason and why it is often incompatible and incomprehensible for outsiders. If we keep thinking of Islam as a religion instead of a nation, we will never understand the nature of the problem with Islam.
We have to understand that Islam is a nationality, not a religion. Muslims are christians but belong to the nation of Islam. Islam is not identical with a religion, but it has a state religion, which is a form of Arian Christianity.
Muslims cannot have any other citizenship but Islam. This means nobody can be a French Muslim or a Nigerian Muslim. He is either French, Nigerian or Muslim.
Muslims are a state on their own and have their own laws, their own language, their own writing, and their own traditions. They will not obey to the laws of other nations. The islamic ummah (community of all muslims) should organize in a way so they can issue their passports to their citizens. Other citizenships and passports need to be revoked.
Since muslims take their laws with them and will not submit to national laws, this has to be taken into consideration when interacting with them. Since different sets of laws apply to citizens of nation states and citizens of "nations of personal loyalties", interactions become quite difficult. Rules for such interactions need to be established from case to case and otherwise must be avoided. A disengagement and segregation between citizens of these totally different concepts of states will be necessary. Muslims must be assigned certain zones where they can live according to their laws, but they should not be allowed to leave these zones as long as they don't become citizens of a nation state and formally resign their loyalty towards Islam (i.e. Arabia). Otherwise a conflict between incompatible sets of law cannot be avoided.
Muslims belong to the Arab nation under the definition of a "nation of personal loyalties" and they should be treated as such. Outside of Greater Arabia they are foreigners and should not be allowed to hold another passport.