Jessica Cheung

And then, in 1974, Palestinian leader Yasser Arafat was invited to speak at the UN for the first time, where he made an appeal to the international community for a Palestinian state.

I was a student, so I brought three... Mansour organized three buses of people to drive from Ohio to New York for the event.

Palestinians were talking about statehood and what it would mean.

And a decade later, Mansour would take a job at the U.N.

and keep pushing for the same goal.

For years, Mansour worked through cycles of Palestinian intifadas and militancy, Israeli retaliation and expanding settlements, new wars, new ceasefires, new peace agreements, like the Oslo Accords, which were seen as the closest the international community came to resolving the conflict.

But in the end, they didn't achieve what they set out to.

When Hamas, in a surprise attack, killed 1,200 people and kidnapped about 250 others.

Pictures emerge of the destroyed Kibbutzim.

Videos of hostages being carried away on the backs of motorcycles and trucks driven by militants.

Stories of people shot in their homes and trapped in burning buildings.

All of it shocked the world.

But after Israel launched the war against Hamas in Gaza, as that war entered its second year with more than 60,000 Palestinians dead and the humanitarian situation worsening, people around the world also saw those pictures and heard those stories, including Mansour, who described what he was seeing in Gaza to the United Nations Security Council this spring.

It was around that time that Mansour said he felt things begin to shift.

And I asked him about that.

Israel denies many of these allegations and strongly refutes the accusation of genocide.

The Israeli delegation didn't come to the meeting.

Their seats stayed empty.

But Mansour was moved to tears.

Throughout the week while I was following Mansour, I kept asking him why this moment felt so important.