Today is the 70th anniversary of the liberation of Auschwitz by the Soviet Union. Postings on Facebook contain the phrase, "never again." Feel free to remember the Holocaust but don't say "never again." Maybe never again for Jews, but there have been dozens of massacres since World War II, including one this month where between 600 and 2,000 people died.
Wikipedia reports 32 massacres since World War II of 500 or more people although I admit that these aren't on the scale of the Holocaust. The Khmer Rouge tried to match the Germans, killing between 1.4 million and 2 million people with another 650,000 Cambodians starving to death. This happened in the 1970s and 1980s, within the lifetime of many people reading this post.
We as a country simply can't keep this from happening. Massacres will keep on happening indefinitely. Repeatedly saying "never again" will not change this. So don't do it.