Palestine
A group that has survived genocide possesses direct knowledge of its harm. When that group chooses to inflict genocide on others they act with full awareness of the suffering they are reproducing.
The crime is not only the destruction of lives and culture but also the conscious disregard of the insight gained through their own history.
In my mind, this makes the act ethically worse than genocide committed in a state of ignorance or stupidity, because it combines atrocity with a conscious rejection of empathy and memory.
You can liken it to comparing a crime of passion killing and a premeditated murder.
Ethical responsibility may not pass automatically through ancestry, but invoking history as ethical currency has consequences. If a state demands recognition and security on the basis of past suffering, it cannot expect impunity when its own actions mirror the crimes it condemns.