What percent of the world's population practice islamism?

Answer 1

It is important to note, first that Islam is a religion, but Islamism is something else. It is a political ideology whose goal is to bring the religious tenets of Islam into the daily functioning of a government and its laws. Islamism is a modern movement whose roots began contemporaneously with the rise of Salafism in the late 1800s and early 1900s in Egypt. Islamism is not by nature violent or expansive. Many Islamist movements have concrete nationalistic goals such as the Islamists in power in Turkey. As a political philosophy, Islamism does not have practitioners, just as Communism and other political philosophies do not have practitioners.

Islam represents roughly 23% of the world's population.