However when looking at the details what they mean is that they are disturbed at immigrants of various backgrounds expressing their beliefs which can potentially contradict Western Laws. Were a law of their own country to contradict with their religious faith, few european would abide by this law. However Western laws have been forged by judeo-christians with some history around the Roman Catholic Church, the Lutheran Church, the Calvinist Church and the Jewish religion. Islam being a much more recent religion and recent immigration in Europe did not have the chance to participate in the process of law making across ages. For this reason, the common imaginary is clearly opposing muslims which have their law: Sharia to western (historical) residents which have their own law. There is no denial that western law is the basis of international organizations whether they relate to economy, to trade, to peace, to human rights or to relief. In the end, the universal reach of these laws have been more and more challenged by radical muslims and most notably during the famous case of the danish caricatures.
But limiting the debate to this superficial facts does not allow a clear understanding. Sharia is not a uniformly stated and applied law, we can even consider that there are as many Sharia laws as there are power to exercise it. So law like in Europe has variations that may fit or not a particular group and that is not different in this aspect. Assertiveness of the most radical versions of texts by the authority of some countries or some communities tends to hide how strong the relations between the religious law and the western law is. There is little doubt that the most developed legal systems of early historical times (Greek, Achaemenid, Roman, ..) influenced the establishment of islamic law. Some of these ideas will later travel back to Europe as part of the Enlightenment and also as part of colonial rule of large European Empires. The legal system is thus not far apart from "western" practice except in one aspect which is the divide between State apparatus and Church/Religion. In most countries with a muslim majority, the structure of government is rigid or archaic and not opened to a re-foundation of the authorities.
The problem is not, as people think spread to all muslims, but the very problem (the one of strategic concern to Western Powers) is that of State supervision of religion. On one side, Europe has grown across time an institutional relationship with various churches or representatives of their religion, outlawed some sects and defined the area in which religious intervention is accepted. On the other side, muslim countries do not have such uses and can be erratic in their approach of other religions (or of variations of the main branch of Islam of the country). Most muslim countries established during the 20th century through a democratic process have been able to establish some kind of separation and do not pretend to rule according to God's law. The "ruler" is not the voice of God but merely observant of the practices of people of the country (and so of their beliefs).
Observance of religion should thus be definitely separated of observance of the religious law from a migrant's home country. And this is the tendency that can be observed in all muslim populations in Europe and in non-Arabic countries. While the problems of some countries are not migrating with their population, the people still become more and more aware of such problems. The only way to solve such issues is to drive by example. This is where the relation between Turkey (the most secularist of the region) and Iran (the most theocratic of the region) has the potential to shift minds should their political interests become aligned.
