The odd thing is, that before the creation of Giorno Unificazione (Unification Day), not many Italians gave much thought to March 17th. It was just a day like any other. Perhaps the reason is because there isn't much national identity in Italy. Look at the vintage cartoon above... That's Garibaldi trying to stuff Victor Emmanuel's foot into the boot of Italy--a tight fit indeed for the many varied cultures living in Italy at the time.
One's regional identity matters more to most Italians. They are Sicilian or Venetian or Calabrese or Tuscan before they are "Italian". One might even argue that the Euro zone has watered down the Italian identity even further... no more pride-inspiring Lire notes with the likenesses of Marco Polo, Raphaello, Marconi or Verdi... Euro notes are homogenized. And today everyone carries the same Euro-style passport as every other Euro country.
Then there are the languages. Italy doesn't speak one national language. There are over 200 recognized dialects spoken in Italy besides Italian. In truth, there are really thousands. (Read about them HERE.) You might be on a train and hear announcements in Italian and one or two local dialects. Someone from Rome might not understand a Calabrese speaking in their native tongue. Even my Napolitano mother couldn't understand when my father spoke his Molfetese dialect. No wonder they brought us up speaking only English.
Today, they are starting to care, if only because it is a guaranteed day off--with pay. In fact, the only way the government could get the holiday's approval was to take away another holiday (Armed Forces/Liberation Day on November 4) to make way for the new one. They wouldn't give the workers yet another day off, so it all balanced out in the end.
So, if you have any national pride in one Italy, give a toast for Unification Day... and all stand for the Italian National Anthem in the video...