How has Qur'an been protected from distortions?!

Allah in Qur'an has promised that Qur'an shall be protected:

We have, without doubt, sent down the Dhekr [Qur'an]; and We will assuredly guard it [from distortions].

(Qur'an, Surah Hejr, verse 9)

Allah is not like us; we make many promises and later, we break some of our promises but Allah never breaks a Promise:

Never does Allah depart from His Promise ...

(Quran, Surah Roome, verse 6,...)

The Prophet Mohammad (PBUH&HP) has also repeatedly confirmed that Qur'an shall always be protected. Protection of Qur'an has different aspects; on the one hand, Quran's words have to be protected from distortions, which in this aspect, the Promise has been fulfilled and all Muslims around the world have been reading the same Qur'an for over 1400 years; on the other hand, the interpretations, the original and hidden meanings and secrets of Qur'an (Ta’wil) also need to be protected, which in this aspect, the 12 infallible Successors of the Prophet (PBUT) have been carrying this serious and celestial responsibility.

The Prophet Mohammad (PBUH&HP) has said:

Allah has chosen and preferred amongst days, Jom'ah (Friday); amongst months, Ramadan; amongst nights, the night of Qadr; amongst all Prophets, me. Allah appointed Ali from me and chose him superior over all Successors of Prophets. Allah selected Hassan and Hossain from Ali; He chose from Hossain, the Successors who ward, distortions of those who exaggerate, additions of those who seek vanity and untruth, and interpretations and Ta'wil of those who mislead people, off Qur'an. The ninth of them [descendants of Hossain] will be the Qaa'em whom all of their open and hidden aspects shall be with him.

(Wasaa’el-O-Shi’ah, Mekyyaal-Ol-Makaarem, ...)

Close your eyes and imagine this world when human hearts will beat in the most peaceful and justful harmony, this world when Qur'an and its Divinely intended interpretations and meanings shall become manifest by Mahdi (may Allah Hasten his wonderful Appearance).