Tisha B'av - Mourning for our loss 2000 years ago?

As Tisha B'av (the Fast of the Ninth of Av) is about to begin we need to realize that we are not commemorating an event or events that took place more than 2000 years ago.
If that were true it would have little or much less meaning today.
Look at the American Holidays that commemorate a past event that have lost much of their significance and they were no more than 200 years old!
For the Fast (or any Jewish Holiday) to have any significance we must realize that they are there to help us correct or improve ourselves based upon current and contemporary issues and wrongdoings.
The Talmud tells us "Any generation that the Temple is not rebuilt in their time it is as if it has been destroyed in their time". We aren't mourning the loss of 2000 years ago and the misdeeds which caused it back then but we are mourning OUR TIMES and the misdeeds that continue to not allow things to permanently change for the best. (the Temple to be rebuilt)
But we shouldn't despair and think that if this corruption is so widespread what can I as one person do?
The answer is alot.
As the prophet Isaiah in last week's Haftora said, that although he refers to the leaders as Lords of Sodom the people are still referred to a "night refuge" in a field and "separated remnant" that there still is some hope, even though it's a small remnant of goodness, they have the power to effect change.
We can effect a change with our efforts regardless of what we think everyone else will do.