An oldie, but goodie. The comments are also interesting.

What happens to society's as the Muslim population grows in percentage of the total?

In the book, Slavery, Terrorism and Islam: The Historical Roots and Contemporary Threat, written by Dr. Peter Hammond, he explores the topic of the impact that an increasing Muslim population has on that society. The lists below illustrate the Muslim population status of countries around the world, and exactly what changes to the societies can be expected according to Hammond.

The book as well as the author are controversial, but the topic is definitely something that needs to be explored and understood. From the book:

As long as the Muslim population remains around or under 2% in any given country, they will be for the most part be regarded as a peace-loving minority, and not as a threat to other citizens. This is the case in:
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LINK