Amid all the controversy over North Korea, Russia, NAFTA, and the Paris Accords, one could argue that President Trump's continued vacillation over the location of the US mission to Israel is the sole conventional aspect of his erratic foreign policy. After all, he is hardly the first Presidential candidate to swear the mission will be moved to Jerusalem if elected, and, as of June 1, 2017, is now the fourth sitting US President to sign a waiver delaying that move for another six months. The source of this predictable, presidential tango is the 1995 Jerusalem Embassy Act, which stipulates the US Embassy must be moved to Jerusalem before May 31, 1999, unless the executive deems a delay "necessary to protect the national security interests of the United States." Since 1999, when the law's provisions came into effect, Presidents Clinton, Bush Jr., and Obama all exercised their discretion to delay the move, either in deference to the peace process, or out of concern the move would spark a violent backlash from the "Arab street." From this perspective, President Trump's decision to defer fulfillment of this particular campaign pledge is not only conventional, but an indication of his commitment to put the safety of America and Americans first.
The problem with this assessment however, is that it understates the national security implications of this particular policy. Relocating the Embassy to Jerusalem will do more than incite anger on the "Arab street," or hamper efforts to restart peace talks between Israelis and Palestinians, it will undercut every national security objective the Trump administration has set out for the region. Carrying out this move before Jerusalem's status has been resolved at the negotiating table will hamper the Trump administration's ability to defeat ISIL, contain Iran's regional ambitions, or even stem the tide of refugees flowing out of the region. Fulfilling this promise, even if enshrined in US domestic law, is also at odds with his determination to restore US clout, and repair relations with traditional US allies he has long charged the Obama administration with alienating. More importantly, while the costs of continuing to double down on this pledge are manifold, there are few discernible gains for his administration--even in terms of the US relationship with Israel.
In the mainstream policy discourse, deferring action on the provisions of the 1995 Jerusalem Embassy Act have typically been justified on preserving the possibility of making headway on the US-mediated peace process, or out of fear outrage in the Arab street would escalate into violence against Americans or American interests at home and abroad. In this respect, the Trump administrations official explanation for signing the waiver--that he made the "decision to maximize the chances of successfully negotiating a deal between Israel and the Palestinians, [and] fulfilling his solemn obligation to defend America's national security interest," is par for the course. It is also a fairly accurate appraisal of the consequences were President Trump to carry out this move in the current regional environment. First, relocating the US embassy to Jerusalem in advance of a negotiated settlement would provoke outrage in the "Arab street." There would likely be riots across the region...