The Argument for Islam is very Simple:

[WinterHold]

No. This topic is to preach about "Shia Islam".
Please, be more obvious.

Whatever, Shia Shiite Sufi, Sunni, Judaism, Christianity, Mormonism all the same bullcrap from the same source.

Not really, there are so many different interpretations that make up the different sects inside the same religion.

Take Muslims; all Muslims believe in the Quran but take other books also to be sources.
So a Sunni would believe in the Quran and to its side. A famous Sunni source:
https://en.wikipedia.org/wiki/Muhammad_al-Bukhari

a Shiite would believe in the Quran and to its side. A famous Shiite source:
https://en.wikipedia.org/wiki/Muhammad_i...al-Kulayni

A Sunni don't agree to Shiite sources.
A Shiite don't agree to Sunni sources.
Pshhhhh war.

There are so many more books. So big, both Shiites and Sunnies take them to be a holly source.
So many other sects, too.

Christians have Catholics, Prostants , Orthodox and to be honest I don't know about the rest. Mrmones? maybe.
Jews have different sects too.

So on, so forth.

Secularism exists because the followers of Abrahamic religions got into a hairy spot. So people got frustrated, and illumination became a fact.
With religions of this size, holes are easily taken advantage of. Who cares about the Quran when you got 16000 Hadiths?

That's why places like the Middle East have grudges that never are quenched, if somebody's religion is hate that is 1400 years old, or 2000 years old or heck: more; how is there any hopes for peace?

They will keep fighting forever.