Board Thread:Naruto Discussions/@comment-37790263-20181211231405/@comment-26636534-20181213112212

@Ultima

Good one.

@ShisuiTheDrownedCrow

On your points 1) and 2). Those were not the main reasons. As @Ultima has said, the main reason was a coup d'etat would have almost certainty have lead to an invasion from another village. That was to be avoided at all costs. So the konoha council decided to allow Shisui to use Koto on Fugaku to avert it.

Danzo disagreed, and instigated his own plan to obtain Shisui's MS and make Itachi kill off his clan by giving him an ultimatum. Itachi followed through to save his brother and because he loved the village, and consequently not segregated by clan lines. This is clear because it happened exactly that way in the manga, there is no opinion to be had of how it actually happened lol.

Note: Not trying to destroy your argument. Many users get confused about this and make up their own versions of characters and events apart from what is canon.