Honestly I think its a silly law. I can say Spain didnt win the World Cup, I can say that Santa exists. Why can't someone doubt that the Turkish at the time had the genocideal idea to murder all Armenians. Just to be clear, the law in Turkey is ridiculous as well. And makes just as little sense.
What is true is that war is never nice and that up till WW1 war was mostly eliminating the enemy by putting complete vilages on fire. After that men 'humanified' war, but in the end war kills. You can make all the 'humanitarian' rules you want, people will die.