About 5 countries among the 56 Muslim nations worldwide implement Islamic criminal laws. Virtually none of them implement sharia in its totality in all spheres of life. Their laws are a combination of local custom and precedent in that particular country, as well as remnants of laws brought by European colonial powers that ruled those countries.
The primary purpose of sharia is to preserve life and order in society, not to incarcerate and punish. Many in the Muslim world who are sick and tired of corruption and injustice demand that the criminal laws of Islam be implemented in their countries. However, this is not what Muslims in America are demanding. Their practice of sharia is limited to the personal sphere.
Sharia Continues to Evolve
Sharia is based on the Qur'an and the teachings of Prophet Muhammad, but not all of sharia is God's word. A good part of sharia is made up of human contributions. There are literally hundreds and thousands of books written in the last 1,400 years, in multiple languages in places as diverse as Timbuktu in Africa to Bukhara in Central Asia, with millions of opinions, judicial reviews, etc. on various issues. Together, they form the body of sharia. Sharia is not one monolithic body or a codified book of comprehensive law, and it evolves over time.
One recent development is a sharia discipline called Islamic Economics and Finance. It now commands a trillion dollar market, thousands of scholarly works, graduate programs, and the establishment of sharia boards at hundreds of Muslim and non-Muslim owned banks. This exercise in sharia is essentially a human contribution of the last 50 years, aiming to offer Muslims guidance on how to invest and conduct their financial transactions in a modern economy in line with their principles as believers.
Throughout history, Islam has cherished debates. An important early Islamic debate that continues today was between traditionalists and rationalists over whether the universal principles of God's law were to be known by revelation or reason or both. These debates have resulted in dozens of schools of thought in Islam.
Islam, like many other faiths, is practiced in a variety of ways by its followers, and sharia continues to be and essential and evolving part of the faith—guiding Muslims on many personal aspects of life. It doesn't serve any purpose to stir up hysteria over sharia taking over in the United States, when the practice of sharia is varying and most often private to Muslims.