Donald Trump used his first international trip as president to visit three of the holiest sites of the world’s three major monotheistic religions. He also used the trip to signal his desire to reach an Israeli-Palestinian peace deal. Apparently, this included U.S. mediation in the recently resolved dispute between Israel and Palestinian prisoners, who ended their seven-week hunger strike on May 26. President Trump has framed his renewed drive for a peace deal as focused on U.S. national security, citing the importance of an Arab alliance with Israel to isolate Iran. But ending the 50-year old Israeli occupation of the West Bank, and enforcing international norms – even when it’s a U.S. ally violating them — is itself a direct and compelling U.S. security interest.

Official U.S. policy, as outlined in the Defense Department’s Law of War Manual, notes “violations of the law of war are counterproductive to the political goals sought to be achieved by military operations.” The Department of Defense, in section of its Law of War Manual, grounds its adherence to International Humanitarian Law in the “golden rule” principle: Do unto others as you would have done to you. It is not necessarily relevant who violates the law (friend or foe) or what specific provision is violated. Any violation undermines international adherence to the law and this directly impacts the safety and wellbeing of our military forces.

International humanitarian law expressly contemplates – and regulates – military occupation. The Fourth Geneva Convention and The Hague Regulations contain explicit provisions setting out an Occupying Power’s legal authority and obligations to the civilians in occupied territory. Israel rejects de jure application of both the Fourth Geneva Convention and The Hague Regulations in the West Bank. In brief, the Israeli theory is that conquered land not previously subject to sovereign authority is not territory governed by the law of occupation. Because Jordan never established sovereignty over the West Bank, Israel’s military control over the territory is not occupation within the meaning of international law. This theory has been rejected in UN Security Council resolutions since 1967, the International Court of Justice’s Wall Advisory Opinion, and in a recent article by former Israeli Ministry of Foreign Affairs Legal Adviser Theodor Meron. And the U.S. Law of War Manual offers no qualification to its position that “[t]territory is considered occupied when it is actually placed under the authority of the hostile forces.”

Israel, given its ultimate control over the entire West Bank, is clearly an “Occupying Power” within the meaning of international humanitarian and customary international law. Many aspects of Israel’s occupation of the West Bank are in conformity with its international obligations. In fact, an Occupying Power has the affirmative duty to administer occupied territory; it must protect the civilian population. For example, the use of military tribunals is specifically authorized under international law. Israel may enact military orders that effectively legislate and exert control over many aspects of life in the West Bank provided it acts in accordance with international law and norms. Article 27 of the Fourth Geneva Convention makes this clear: “protected persons are entitled, in all circumstances, to respect for their persons, their honor, their family rights, their religious convictions and practices, and their manners and customs.” This is the golden rule of military occupation – a rule that the U.S. should demand its enemies and its allies obey.

Military occupation serves a twofold purpose: It is a lawful means of furthering an Occupying Power’s military objectives during armed conflict while requiring the protection of civilian interests (Israeli and Palestinian alike) at all times. Although Israel has held out the notion that an equal partner is required to resolve lingering disputes from the 1967 Arab-Israeli war, international law vests the obligation to protect the interests and welfare of the occupied civilians with the Occupying Power. International humanitarian law regulates the exercise of this obligation and insists that the interests of civilian populations remain paramount. Despite interim agreements between Israel and Palestinian negotiators, Israel retains ultimate control over the entire West Bank. Its military exercises effective control over Areas A, B, and C and all ports of entry. The ball is solidly in Israel’s court; it has the proverbial upper hand and the ability to shape the destiny of the entire civilian population from the Mediterranean Sea to the Jordan River.

But what can compel Israel to end its 50-year occupation? There is no time limit set for occupations under either international humanitarian or customary international law. Instead, Israel and the international community should consider two points. First, state practice matters in determining the norms that govern occupation. International humanitarian law provides the basic structure, but state practice fleshes out the means, methods, and norms. Second, perpetual occupation devoid of meaningful steps towards resolution creates inherent instability. The administration of the occupying power is intended to protect civilians in the aftermath of hostilities. It is not a system of governance or an acceptable means of ensuring the long-term protection of a civilian population’s human rights.

The United States is no stranger to military occupation. The United States occupied Germany for 10 years and Japan for seven years following World War Two. In the latter case, the U.S. wrote the modern constitution still in force in Japan. It’s notable that this document – which the Japanese are loath to reopen in most cases – forbids Japan from engaging in offensive warfare. More recently, the U.S. and its allies were formally recognized as Occupying Powers in Iraq following its invasion in 2003. During the occupation, the U.S.-led Coalition Provisional Authority issued regulations not unlike those issued by the Israel Defense Force in the West Bank. Iraqi domestic law and criminal code were modified and political parties prohibited from assuming power in any new Iraqi-led government. While the U.S. occupation of Iraq is certainly not above criticism from a human rights standpoint, its temporary nature was clear from its inception; it was styled the Coalition Provisional Authority and lasted just shy of one year. These examples of state practice demonstrate what the U.S. has affirmatively described as the “essentially provisional” nature of all occupations.

State practice confirms the underlying rationale of military occupation. Occupying Powers are obligated under international law and norms to act in the best interests of the occupied people. This must mean more than occupation ad infinitum. The rule of law and the international norms undergirding the entire international humanitarian law framework compel Israel to end its occupation. Occupying powers, except for those that have affected illegal annexations, have always brought about this result. In some cases, the result is the imposition of an entire constitutional system that expressly forbids offensive warfare. In other cases, a politically reformed national government was permitted to reconstitute itself. But in all cases, the Occupying Powers took concrete and affirmative steps to end their military occupation. And they did so with the explicit intent of ensuring respect for human rights and the inherent rights of the civilian population.

Conflict between Israel and Palestinians living under occupation is inherently destabilizing. Occupation ad infinitum undermines whatever post-hostility civilian protection features the law of occupation commands. This writing need not concern itself with the various geopolitical power plays possible to enhance regional security. It is sufficient to note the persistent volatility of the region is, at least in part, a product of Israel’s military occupation. Former General David Petraeus acknowledged as much in 2010 when he testified before Congress on the link between the Israeli occupation and U.S. security. This is a natural result whenever human rights are suppressed whether or not the suppression is justified. Israel argues its military courts, orders, and certain security measures are legal restrictions imposed on Palestinians for the safety and security of Israel and the Palestinians themselves. Some of these measures may be viewed as lawful measures when viewed in isolation. But what might be necessary and proportionate during the first five or ten years of occupation cannot remain so fifty years on; even otherwise lawful measures become impermissibly repressive of human rights.

None of this is to say an end to Israeli occupation of the West Bank will end tumult in the Middle East. Syria, Iran, and the battle against Islamist extremism will not be resolved if and when Israel ends its occupation of the West Bank. But Israel and Palestine are important players in the region. Occupation erodes their capacity to engage on broader issues on a daily basis. And prolonged or indefinite occupation inflicts an intergenerational harm on the Palestinian people. Occupations are “essentially provisional” in large part to avoid just such a harm.

Upholding and strengthening the norms of international humanitarian law are vital and unquestionably in the interests of the United States. The millions of men and women serving our country deserve no less. Although international law places no time limit on military occupation, prolonged occupations clearly undermine the rule of law and violate norms of established state practice. Israel, as the Occupying Power, bears the ultimate responsibility for ending the occupation. It can no longer demand a politically equal negotiating partner – no such partner exists so long as Israel controls every facet of life in the West Bank. Perhaps the international community has had it wrong for so many years: negotiations and accords are a nicety, but ultimately Israel can and must decide to end its occupation and do so consistent with international law.

Image: Getty/Lior Mizrahi