Palestinians consider Jerusalem, or Al Quds, as their own capital of the Palestinian state, creating competing claims on the holy city. Proposed solutions to Jerusalem are numerous, but some sort of division between West (where most Jews live) and East (where most Palestinians live) is thought to be essential to any two state outcome, with perhaps a special status accorded to the holy sites.
Now that a two state solution seems nowhere on the horizon, any moves that would legitimize Israel's claim over the entire city would be considered by most states of the region and beyond as a provocative act of the United States siding with Israel.
But there are greater concerns today beyond undermining the U.S. role in a broken peace process that few have hope of reviving anytime soon. And those touch on core national security interests of both the United States and its key regional allies, including Israel.
Such a move would be a boon for the multiple jihadi groups across the region. Despite the Palestinian issue nearly dropping off the map in the Arab world, the emotional draw of Al Quds continues to resonate across the Muslim world, just as Jerusalem does for Christians and Jews. Extremists in the region capitalize on this, including Al Quds in jihadi narratives seeking to oust Western influence and Western-backed rulers from the region.
With the United States currently engaged in a difficult military battle alongside regional anti-ISIS coalition partners to retake Mosul and eventually Raqqa from ISIS, not to mention the concern over terrorism in Europe and North America, the timing of an embassy move couldn't be worse.
And then there's the consideration of the political sensitivities of key U.S. allies in the region, particularly Jordan. Jordan has a special tie to Jerusalem based on the Hashemite family's historic role as guardian of the Islamic holy sites and has publicly opposed any change of status of the city outside a negotiated settlement.
An embassy move might well inflame Jordan's population, creating even more pressures on the Jordanian government, which already is battling ISIS and other jihadists forces and bearing a tremendous burden from the Syrian refugee crisis. Jordan's stability is a core U.S. and Israeli national security interest.
At a time when Middle East states are crumbling, does it make sense to risk the stability of a key partner in fighting regional extremism? Would a Jordanian government be able to maintain the same level of diplomatic relations with Washington or continue to host U.S. counter-terrorist forces and training programs after such a provocative move?
Such a move would almost certainly antagonize many other partners in the Islamic world who are key to fighting ISIS and other extremists.