Few nations, if any, have stood by their Jewish community as the Danish people did during the Holocaust.
For three years during German occupation, they stood strong against Nazi demands to persecute the local Jews. When the order came to arrest and deport the 8,000-strong community to Theresienstadt, a rescue operation, financed by the Danish royal family, was set in motion and nearly all the Jews were ferried by night in small boats to neutral Sweden. The 450 who were deported continued to be protected and fed by the Danish authorities.
Less than one per cent perished - the smallest number of Holocaust victims in any country occupied by Germany.
The thousands of ordinary Danish citizens who gathered in the cold outside the main synagogue of Copenhagen this week following the murder of Dan Uzan, the volunteer security guard shot in a terror attack outside the shul on Saturday night, were worthy successors of this unique tradition.
And it was echoed by their leaders, including Prime Minister Helle Thorning-Schmidt, who said on Monday that "an attack on the Jewish community in Denmark is an attack on all Denmark".
It was the kind of thing politicians say at such moments but in a country such as Denmark - and there are no other such countries - we can allow ourselves to believe Ms Thorning-Schmidt sincerely meant it.
But at the same time, Denmark last weekend failed its Jews. It was not alone in its failure; rather it merely takes its place in a more general failing of Western Europe.
Nine and a half years ago, Britain recieved a stark warning in the form of the 7/7 bombings. It was a warning about the existence of a homegrown terror threat; of young men who speak the local language with the correct accent, hold the right passport and know their way around the main roads and back alleys, and are prepared to slaughter their fellow-citizens.
As Europe failed to heed this warning, the threat has increased. The numbers of jihadis have grown and they have received more sophisticated guidance, first from al Qaeda and then from Islamic State. Following the attacks in Toulouse in 2012, they increasingly became focused on Jewish targets, along with those who symbolised freedom of speech and the armed forces of these countries.
It is a conceptual failure since it is not enough just to add more police around synagogues (as was done in Copenhagen, though probably too little and too late), since not every Jewish target can be protected and the security measures often will not deter a determined murderer.
There has been a failure to realise that this is both a communal problem, which has to be tackled at the local level of disaffected immigrant communities; and as a continent-wide challenge, which necessitates an effective network of intelligence-sharing and joint monitoring to detect young men and women who are planning to travel and join the jihadists in Syria and Iraq, or those who have returned.
These efforts are being made but nowhere near enough resources have been allocated. Neither have Europe's parliaments made the necessary changes in legislation. The EU, normally eager to set up new pan-European agencies, has yet to establish an effective framework that can pool information and co-ordinate surveillance.
Time after time - in Toulouse, Brussels, Paris and Copenhagen - it transpired that the murderers had been known to the security services, that they had often already served time, and yet they evaded detection because they were allowed to slip off the radar.
When the leaders of the Jewish community in Denmark asked the Ministry of Justice to reassess the threat level to Jews following the Paris attack, they were told that "you already have the highest level of security". This was true; the state-of-art security systems that surround the synagogue are financed by the Danish government. The armed police at the entrance to the shul, along with Dan Uzan, prevented a much larger tragedy occurring.
The failure was that the Danish government was late to realise that their "highest level of security" is insufficient to deal with the threat that has been facing Europe for years now.