WWI in fact began on 28 July, not Aug 1 (9th Av) in 1914. The first Warsaw ghetto liquidation order was for made for 22 July and carried out 24 July, not the 23rd of July, which was the 9th of Av. On the 23rd, the Jewish underground met and decided on resistance. We had too many tragedies to fit on one day!
Palestinian teen arrested for allegedly rioting in East Jerusalem (Haaretz)
from the article: Why I Still Fast on Tisha B’Av