US Diplomacy should always play a role in security and peace in all parts of the world. Why in Israel and Palestine? When the United States gets involved its able to push nations states out of the diplomatic role that have ulterior motive against American Allies.
Mediating negotiations is key for brining stability and peace to a volatile region. The US could use leverages that other nations states do not posses for example, food aid, money, and political pressure.
In the years past since the found of Israel the US has been growing in its diplomatic role in Israel and the Near East.
The wars that came as a result in the founding of the nation state Israel and a Cold War world propelled the United States to play a active diplomatic and military role in the region by making new allies in the region.
As far as creating a resolution or solving the problem of land, peace, and nation states. This will not be solved within one Presidential administration. But the US needs to keep certain objectives, purpose, goals and stop flip flopping goals in the Israeli-Palestinian conflict.