Why can tribes also kill Prince Kael'thas, the blood elf?

The history of Storm Fort does not explain why the blood elves wanted to kill Kael'thas.

Kael'thas used to be the leader of the blood elves, but he was only the professional leader of the legal system of the blood elves. From the disaster in Quel 'Salas, some blood elves felt the crisis of magic. Even now, Silver Moon City is secretly divided into two factions, one with Kael'thas as the main mage and the other with the rangers led by former sylvanas windrunner subordinates. Silver Moon City seems to be harmonious. In fact, even if Kael'thas returns here, it is still unknown whether the blood elves' regime will be consolidated.

Secondly, as the base of Lu Na, Kael'thas captured the storm fortress and forged a great hatred with Lu Na, while another blood elf force, the fortune teller, left Kael'thas to take refuge. In fact, it is obvious that the blood elves have been divided into three factions, one of which is still attached to Kael'thas, one is secretly trying to transform the blood elves with a new pattern, and the other is openly confronting Kael'thas. In such a complicated situation,