R' Wolpoe speculates that Sukkot celebrates the dedication of the First Temple by King Solomon, which occurred on Sukkot (see I Kings 8). He bolsters this with the idea that the saddest day of the year, 9 Av, commemorates the destruction of the Temple[s], therefore the day that is defined as Z'man Simchateinu, the time of our rejoicing, commemorates the dedication of the Temple.
This doesn't work for me. It seems backwards.
Shlomo Hamelech presumably scheduled the dedication for Sukkot because people would already have to be in
The Exodus' timing was God's idea. The timing of the giving of the Torah was also God's idea. Both predate the actual giving of the mitzvoth of Pesach and Shavuot. The timing of the
a) not until 487+ years after the festival of Sukkot was ordained;
b) arranged by Shlomo haMelech for the convenience of the olim laregel.
Chanukah happening when it did, on the anniversary of Zerubavel's Aliyah movement, that was the hand of God. Well, actually, it was the Maccabees scheduling it, since they retook the
So Sukkot is *not* a commemoration of the dedication of the
On the contrary, rejoicing on Sukkot is part of the Biblical definition of the holiday, therefore predating the First Temple by almost 500 years. Rejoicing is understood by Chazal in many ways - over economic plenty (the harvest festival), over successful completion of the Teshuvah season (which then explains why Shmini Atzeret is also Zman Simchateinu - because it comes after the close of the appeals period, on Hoshana Rabba), and ach sameiach, an incomplete rejoicing because we are in the real world where life always intervenes.
Further, the Mishkan was set up on 1 Nissan, the Second Temple was dedicated on 3 Adar, the Maccabean Temple was dedicated on 25 Kislev, and here the First Temple was dedicated on Sukkot. So there's no single day devoted to commemorating the Temple's dedication, as there is to the two Destructions.