Why a weapon-free Jerusalem?

The psalmist sang his longing - “Pray for the peace of Jerusalem: they shall prosper that love thee”. Psalm 122:6.

Even today Old Jerusalem is a cosmopolitan neighbourhood. Black-coated Hasidim rub shoulders with robed Christian priests and Muslims in traditional dress. But guns are here, there and everywhere. Over the shoulders of worshippers at the Wailing Wall. In the hands of watchful Israeli conscripts. The psalmist's dream, and ours, will not be realized until these weapons are removed from the Holy City.
Why does a weapon-free Jerusalem have to remain just a dream? The Old City is bounded by an ancient wall penetrated by eight “gates”. One can envision a couple of airport security systems outside each gate, staffed independently by Israelis and Palestinians. If an aircraft can be weapon-free, why not Old Jerusalem?
Count the benefits. Pilgrims of every faith would come and go without fear of guns or bombs. Tourists would return to the old markets. Mosques, churches and synagogues would become havens of peace once more.
Remember: Jerusalem is a Holy City, for Muslims, for Christians and for Jews. Their combined prayers, their longing for peace, the dedicated conscience of the three Abrahamic faiths could launch such a compelling bandwagon that politicians (and even cautious church dignitaries) would hasten to climb on board. Jubilee 2000 should remind us: the pressure must come from below.

Why is this urgent?
How can Quakers help to bring this about?