Board Thread:Wiki Discussions and Support/@comment-142748-20141231093731/@comment-25892920-20150104025023

ItachiWasAHero wrote: AND Shisui was an Anbu under the Hokage too. But Itachi was only able to get to Captain position because he was a genius prodigy, combined with the fact he was a spy for Hiruzen.

Many people were ANBU under Hiruzen, also Hiruzen commands fresh Genins out of the Academy to D-rank mission. ANBU hold no power position to influence the Hokage unlike the commander, who is shown to have a say in the Land of Fire Politics. Agree Itachi was a prodigy, but having someone like Fugaku, surely helps.