When the Oslo process was devised, the status of Jerusalem, with the other Israeli-Palestinian intractables, was set aside until later.
For Arabs, there can be no equitable peace until East Jerusalem, taken by the Israelis in 1967, is returned. For Israelis, the divided city was unified in '67 and the mystical bonds between Jews and Solomon's Temple were recreated on earth.
To add to the fraught nature of Jerusalem politics, the Jews' 'Temple Mount' houses the Muslims' 'Noble Sanctuary', third holiest site in Islam after Makkah and Medinah.
Almost the entire Israeli political spectrum agrees that Jerusalem should remain in Jewish hands. However, most of the international community deems Israel's annexation of East Jerusalem illegal. Only Costa Rica and El Salvador have moved their embassies from Tel Aviv to Jerusalem.
In the absence of a settlement, Jerusalem is dynamite to the peace process.