The main event marking the city's unification is the Flag Dance, a parade of youth, waving Israeli flags, as they make their way through the streets leading into the old city and the narrow allies, heading to the Western Wall where a rally is held.
This has become a yearly show of hooliganism by some. They may not be the majority of participants, but they have become the loudest and most conspicuous among them.
If today, once again, their offensive and provocative chants directed against the Palestinian residents of the city, are allowed, they will be doing the work of Israel haters and anti-Semites, with their own voices.
Jerusalem is not an easy town. It is plagued by conflict. In the past, the tension was between European Jews and those coming from Arab and North African countries, which begat the social protest movement, Black Pantherst.
The Haredi communities have always conflicted with religious and non-religious alike, on issues ranging from observance of the Sabbath to their brand of modesty. These have always been and will probably continue to be, points of contention.
And finally, the Israeli Palestinian conflict is centered in Jerusalem. The united city that is fragmented, where Jews still avoid many of its quarters.
Public opinion polling has shown, in the past, a majority of Palestinians prefer to remain under Israeli sovereignty. But the majority does not decide. A loud and violent minority does.
In today's parade again among the thousands marching, only a small minority will show their racist, hateful behavior, but they will set the tone for everyone else and their leadership will do little to stop it.
There has been an ongoing argument whether the parade should be allowed to pass through the Moslem areas of the city. If the organizers insist on that route, they must then bear the responsibility for causing the provocation.
Imagine the reverse. Imagine Nakba Day, marking the Palestinian catastrophe that was born out of the foundation of Israel. Imagine Palestinians allowed to march through Jewish quarters, while a relatively small number of participant chant "death to Jews". Would the fact they were a minority within the group, be an acceptable defense?
Jerusalem Day's style of hooliganism is not unique to Israel. Every year the Orange Walk in Belfast organized by a political party, continues to pass through Catholic neighborhoods causing worry and tension.
The Jerusalem Day Flag Dance too was initially organized, by a political organization promoting religious nationalism. They petitioned the Supreme Court to march through Moslem quarters claiming freedom of expression and were granted the right to do so.
Now, however, the parade has become part of the municipality's program of events and the funding for it, is mostly from the municipal budget. Why then has the city not demanded the parade avoid provocation and remain in Jewish parts of town?
If today's events allow hooligans to spread their hate, it will be Jerusalem that pays the price