Perhaps you know the word for basis or foundation, in the more abstract sense: יְסוֹד (yeh-SOHD).
There's another word, however, for the foundation or infrastructure of a house, a city, a state, etc: תַּשְׁתִּית (tahsh-TEET), such that Israel's Ministry of Infrastructure(s) is מִשְׂרַד הַתַּשְׁתִּיוֹת (mees-RAHD hah-tahsh-tee-YOHT).
Over the past three weeks, I've been featuring words and concepts that I believe help form the תשתית of that which the Jews are mourning - and hoping for - today. The Temple itself is just a facade without this תשתית; but with this תשתית, the Temple becomes the world's beacon of goodness, of life, of kindness...
So, to review (as we're apt to do often in Ulpan La-Inyan), here are some of the words I believe can form the תשתית of the Temple:
May this תִּשְׁעָה בְּאָב (teesh-AH beh-AHV) - ninth of Av - be the last one where the Jews are mourning. May it be a great celebration next time around.
I believe it's up to us to create the reason for celebration.