I will always support that any leader that encourage genocide or war should be punished seriously because they are not the once to suffer or die with it gets serious.
Say no to genocide
You say it like it to so so easy forgetting the fact that before such things happen, there is definitely a hidden agenda. The reasons for genocide might not only be for dominance but to control the economy of the weaker state.
Do you think a President of a nation will see an opportunity to lift his nation's economy and not grab it?