This is interesting too regarding asara b'tevet:
QUOTE
On this day, the siege of Jerusalem began during the reign of Nebuchadnezzar, prior to the destruction of the First Temple. The citizens of Jerusalem knew hunger as never before...
This sad day was proclaimed a fast by the rabbis to commemorate the Destruction of the Temple and the consequent dispersion. The sages pointed out that the day should be devoted to contemplation of the events leading up to the siege.
In our day: The 10th Tevet has been established in Israel by the Chief Rabbinate as the day of mourning for all those who perished in the Holocaust and whose day of departure from this world (yahrzeit) is unknown. The day is marked by special educational programs in the schools.
(Virtual Jerusalem, Holidays)
Jeremiah 52:4-6
And it came to pass in the ninth year of his reign, in the tenth month [Dec/Jan], in the tenth day of the month, that Nebuchadrezzar king of Babylon came, he and all his army, against Jerusalem, and pitched against it, and built forts, against it round about. So the city was besieged unto the eleventh year of king Zedekiah [about 18 months].
The month of Tevet is the darkest time of the year. Its days are the shortest of the year and its nights the longest. The tribe associated with Tevet is the tribe of Dan. When the Children of Israel traveled and camped in the desert, they encircled the Holy Ark. The tribe of Dan was the most northerly encampment. The North is a dark cold place. The long nights of Tevet are even longer in the North. The Hebrew word for North -- tzafon -- is spelled the same as tzafun -- which means hidden. The Talmud tells us that one of the names of the yetzer hara -- the negative drive -- is tzafuni (Succa 52).
Beginning on the eighth of Tevet, three days of spiritual darkness descended on the world. The first darkness was the translation into Greek of the Torah. King Ptolemy took 70 great Torah Sages and confined them in separate cubicles and instructed them to translate the Torah. Hence its name -- the Septuagint. With the translation of the Torah into Greek, the "lion which had been roaming free was put into a cage." The radiance of the Torah which shines through the sentences, the words and the letters of the Holy tongue, was shuttered into a closed room, its light constricted and obfuscated. For however accurate a translation may be, the Torah's fathomless depths, its mystical secrets, become truncated and lost when it speaks in another tongue.
The second day of darkness was the passing from this world of Ezra the Sofer on the ninth of Tevet. Ezra was among the last of the prophets. It was he who gave the Torah the letters that we recognize today -- Ashurit script. By employing Ashurit, Ezra made the Torah accessible to all the people. The Torah's light was able to shine out to the least scholarly of the Jewish People. It was also Ezra who instituted the public reading of the Torah on Mondays, Thursdays and at mincha on Shabbat. Ezra brought Torah to the people. When his light went out on the ninth of Tevet, the world became darker, and the Torah -- more constrained and confined.
On the tenth of Tevet, the armies of the Babylonian emperor, Nevuchadnetzar, led by his general Nevuzaradan began the siege on Jerusalem, resulting in the destruction of the first Holy Temple and the exile of the Jewish people to Babylon.
If you think about it, on the tenth of Tevet itself, ostensibly, nothing really tragic happened. No wall was breached. No one died. Not a shot was fired. Only the siege was begun.
What is really interesting is that this all pertains to divrey Torah and the two paths before us:
1. bringing light from darkness (revealing hidden truth)
2. or creating more darkness (hiding the truth)