I have to agree with Lysistrata.
To state that in "30-40 years no one will remember", is a ludicrous statement to make.
The Holocaust, and by extension Nazi Germany, enjoys the distinction of being one of the most well documented atrocities in human history. At the Eichmann trial in Jerusalem in 1960-61, the prosecution presented over 2.5 TONS of documents bearing his signature.
For those of you who don't know, Adolf Eichmann was a Gestapo Officer in charge of Dept 4BIV, or the Gestapo's Office of Jewish Affairs. He department controlled the ghettos and was directly responsible for drawing up the lists for transport to the camps. On Israel's Most Wanted List, he was number four, after Hitler, Bormann and Muller.
Even today on BBC, I read this:
http://www.bbc.com/news/world-europe-42144186
The Nazi state and its activities (to which the Swastika is linked), had a profound impact on international law.
The 1951 UN Convention on the Prevention and Punishment of the Crime of Genocide. It stems from that period, and has served as a the basis for indictments for Crimes of Genocide.
Look at what just happened in the IJC or The Hague. The conclusion of 16 years of trials for war crimes (including genocide), in the former Yugoslavia.
Its impact on the Laws of Armed Conflict. One of the central pillars of the LOAC, something every member of every NATO military has sworn to abide by, is the Nuremberg Principle. That just following orders, is no defence.
Because of the monstrosity of the crimes committed by the Nazis, has made us more aware of the necessity of speaking up and openly condemning these acts.
For example, the Armenian Genocide (1915-1917), 1.5 million Armenians were murdered by Turkey. Even though we were at war with Turkey, nothing was said, Turkey was never formally condemned (at the time), for its actions.
The Holocaust spurned no response from the Allies. Yes, we knew about it. Churchill and Roosevelt were both briefed in 1942 about mass killings of Jews. There was a wealth of intelligence concerning Nazi activities.
Compare that, to the response to two recent genocides. The Rohingya in Myanmar. Look how fast the world condemned Myanmar for its actions. Look at how fast the UNHCR got involved. People are demanding that Aung San Suu Ky be stripped of her Nobel Prize because she refused to speak up.
https://www.theatlantic.com/international/archive/2017/09/aung-san-suu-kyi-nobel-prize/540453/
The Darfur Genocide, they have been condemned by the UN and just about every other world government. The African Union has peacekeepers in the region.
https://www.hmh.org/la_genocide_darfur.shtml