Israel-Turkey Relations Nearing a Rupture

For reasons both political and personal, the killing of Hamas leader Ismail Haniyeh last week may represent a turning point in Turkey’s ties with Israel. In addition to Ankara’s nearly twenty-year relationship with and support for Hamas, President Recep Tayyip Erdogan knew Haniyeh well, treating him like a family member and protege. In fact, Erdogan had just invited Haniyeh to address parliament shortly before his death, exacerbating the shock and embarrassment of his sudden demise. As such, Erdogan will almost certainly treat the assassination as a personal slight and instruct his bureaucrats to harden the government’s stance toward Israel. Turkish foreign policy decisionmakers and the broader population will back this shift, since many of them already viewed Israel’s campaign against Hamas in the Gaza Strip as misplaced, ill-executed, and stained by civilian casualties.

As a first punitive step, Turkey joined South Africa’s International Court of Justice case against Israel on August 7, aiming to prosecute the country for allegedly committing genocide in Gaza. Although Ankara’s ICJ submission reportedly avoided a commitment to accept the court’s eventual judgment as binding, the high-profile diplomatic move is a sign that other Turkish measures are forthcoming, with probable implications for U.S. policy and Israel-Turkey relations alike.

Two Decades of Ties with Hamas

Erdogan first established formal contacts with Hamas rather early in his long reign as Turkey’s head of state, inviting the group’s then-leader Khaled Mashal to Ankara in 2006. At the time, Turkey had excellent ties with Israel, rooted in its 1949 recognition of the Jewish state (for decades, Turkey was Israel’s only Muslim-majority friend). The relationship had also experienced a growth spurt during the 1990s, including a large increase in Israeli tourism to Turkey, various free-trade agreements, high-level visits, and deep intelligence and military cooperation.

Yet these strong ties did not translate into an anti-Palestinian stance—historically, Turkey supported the Palestinian cause even as it developed good relations with Israel. For instance, it established formal ties with the Palestine Liberation Organization in the late 1970s and was among the first countries to recognize the “State of Palestine” in exile in 1988. Ankara also backed the Palestinian Authority after it was established as part of the Oslo peace process in the 1990s.

This dynamic underwent a notable shift after the turn of the century—partly due to Israel’s multiple military clashes with Hamas, but also because Erdogan prioritized ties with the group at the expense of other Palestinian factions, including Fatah, the PA’s leading party. Unlike Israel, the United States, and many other governments, Ankara does not view Hamas as an illegitimate terrorist group, but rather as a legitimate voice of the Palestinian people and a key actor in the struggle against Israel. Hence, Ankara began hosting Hamas officials, first semi-secretly and then quite openly (though it refrained from hosting the group’s top leaders).

Long before the current Gaza war, each cycle of combat in the Strip eroded Turkish goodwill toward Israel, while Ankara’s efforts to help Hamas increasingly angered Jerusalem. As a result, the bilateral relationship has been gradually downgraded from excellent to nearly ruptured. The rift widened into a chasm in 2010, after an “international flotilla” of privately owned ships sailed from Turkey with the aim of ending Israel’s blockade against Hamas-controlled Gaza. When Israeli commandoes boarded the ships, clashes erupted and eight Turkish citizens were killed, along with one U.S.-Turkish dual national. The two countries then severed their diplomatic relations, which were not fully restored until December 2022 after years of U.S. mediation. As part of that reset, Turkey committed to curbing Hamas’s presence on its soil, but the current Gaza war and the Haniyeh assassination threaten to upend all that progress and throw the relationship into an even deeper abyss. And this time, Washington will be hard-pressed to bring it back from the brink.

Ankara’s Likely Punitive Measures

Turkey has been taking various actions against Israel since the military campaign in Gaza first began last year, and these measures are set to intensify following the Haniyeh incident. On the diplomatic front, Erdogan has joined other officials in directing harsh rhetoric toward Israel throughout the war, including a May 13 statement accusing it of genocide. On the economic front, Ankara issued a suite of trade restrictions on April 9, then banned all import and export activity with Israel on May 2, announcing that the boycott would persist until a “permanent ceasefire and humanitarian aid are secured in Gaza.”

In response to Haniyeh’s killing, Turkey could widen its toolbox against Israel in several ways:

Blocking NATO cooperation. In addition to joining the ICJ case, Turkey will likely force a full moratorium on NATO cooperation with Israel. The alliance requires unanimous member approval of all decisions, so Ankara has reportedly been able to veto various forms of cooperation since the Gaza war began (e.g., joint meetings and exercises). Although it has stopped short of a full moratorium and allowed certain symbolic measures to pass (e.g., joint statements about the October 7 attack), it may now decide to permanently veto all Israel-related initiates going forward.

Trade sanctions and airspace restrictions. Ankara could clamp down further on the May 2 boycott, closing the loophole that has allowed many Turkish companies to use third countries (e.g., Greece) to continue trading with Israel. It could also cut energy flows from its Mediterranean terminal of Ceyhan, where oil brought in from Azerbaijan via pipeline is currently shipped to Israel. Last but not least, Turkey may consider closing its airspace to commercial planes flying to and from Israel.

“Nuclear” options. Other potential actions could prove serious enough to rupture the relationship indefinitely. For example, a new flotilla has been anchored in Istanbul for months awaiting permission to sail to Gaza and undermine Israel’s blockade; Turkey could decide to give it the green light. Given that the Strip is currently an active war zone, Israel would no doubt confront this flotilla militarily, likely resulting in a repeat of the deadly 2010 confrontation or worse. Other “nuclear” options could include hosting Hamas’s top leadership openly and formally or suspending diplomatic ties with Israel.

Israel’s Options

One important dynamic that may limit Turkish retaliation is Erdogan’s desire to play a role in Gaza “the day after.” Ankara is eager to participate in reconstructing the Strip, sorting out Palestinian politics, and mediating a long-term solution to the Israeli-Palestinian conflict—both to help the Palestinian people and to cement itself as a regional power. Hence, if Israel sends signals through regional mediators (e.g., the United Arab Emirates) that there could be a role for Turkey in shaping Gaza’s future, Erdogan may be reticent to launch the deeper economic sanctions or “nuclear” options described above.

Even in that scenario, however, Turkey would continue censuring Israel internationally, and Jerusalem may prove unwilling to tolerate further diplomatic rebukes without responding. For example, it might decide to censure Ankara right back—forcefully and consistently—or take actions that threaten Turkish interests in the East Mediterranean, such as doubling down on its alliance with Greece. This could anger Erdogan to the point where he resorts to deeper sanctions after all, among other serious options. Such escalation would in turn trigger problems for U.S.-Turkey relations—especially in Congress, where pro-Greece and pro-Israel voices are traditionally stronger than pro-Turkey voices. Taken together, these developments would almost certainly take the Israel-Turkey relationship across the Rubicon of reparability.

Implications for U.S. Policy

The United States has few direct and immediately effective tools to prevent an Israel-Turkey rupture, but it needs to bring out the full kit given the potentially serious multilateral consequences. One option is to consult with the UAE, which is an ally of both Israel and Turkey and can counsel them to avoid steps that might destroy their mutual ties. Another option is to reserve space in advance for vetted Turkish NGOs to take part in Gaza’s eventual reconstruction, working with Israel and other stakeholders such as the UAE, Egypt, and the European Union.

The Biden administration should also enhance the messaging between its cabinet-level officials and their Turkish and Israeli counterparts. For example, they should ask Israeli officials to refrain from politically inflammatory public statements like the recent tweet by Foreign Minister Israel Katz, who called Erdogan an “anti-Semitic dictator” and seemingly tried to stoke competition between the president and his domestic opposition—a strategy that is bound to create backlash among a Turkish public rightly sensitive to foreign interference in its politics. After the previous rupture in 2010, it took multiple U.S. administrations over a decade to put the pieces of the Israel-Turkey relationship back together, so Washington must do what it can to keep the peace between two key allies.

Soner Cagaptay is the Beyer Family Senior Fellow at The Washington Institute and director of its Turkish Research Program.