Asarah B’Teves is the day that the wicked Babylonian king Nevuchadnetzar started his siege of Yerushalayim, foreshadowing the beginning of the end of the first Beis Hamikdash, which culminated with its destruction on Tisha B’Av several years later.
Therefore, Chazal declared it a public fast, one of four public fast days that memorialize different aspects of the catastrophes and national tragedies associated with the destruction of both Batei HaMikdash. Ohr Somayach
A General “Day of Kaddish” Proposal
So massive was the scale of the Holocaust killing and so reckless its speed that for most of the dead there was no firm knowledge of the Yahrzeit, the actual date of death. Indeed, for many of the dead there were no survivors of the immediate family to say.
In 1948, the Israeli rabbinate proposed a Yom Kaddish Klali, a general Day of Kaddish to be said for all those for whom there were relatives to say the prayer but no known date of death, and for those for whom there was no relative to say Kaddish but others would say it for them.
Given the high number of victims in the above two categories, the rabbinate also proposed that this communal Kaddish day be the day of Holocaust commemoration. The day chosen was Asarah Bteves. MJL
Ultimately, the State of Israel created a Yom Hashoah to exclusively commemorate the victims of the Holocaust.
Nonetheless, all of the individual and communal tragedies suffered by yidden, since the churban until this very day, has to be viewed as being a direct outcome of the Churban Beis Hamikdosh.
The more we will appreciate how much we are lacking in our daily lives due to the absence of the Beis Hamikdosh, the closer we will come to it’s rebuilding.
שיבנה בית נמקדש במהרה בימינו אמן