Islam is not protected by the First Amendment. The reason that it is not protected by the First Amendment is that Islam is not a religion. Historical research reveals that the founding fathers defined religion as:

A system of worship of God that does not persecute people of other religions.

One of the main teachings of Islam is:

The persecution of people of other religions.

Therefore:

Islam is not a religion.

Therefore:

Islam is not protected by the First Amendment.