Israeli Prime Minister Benjamin Netanyahu and Saudi Crown Prince Mohammed bin Salman reportedly met in secret with Secretary of State Mike Pompeo on Sunday evening. This has been denied officially by Saudi sources, but it would be consistent with the recent trend of rapprochement between the historic enemies. This development — a de facto anti-Iranian alliance between Israel and the Gulf Arab kingdoms — will likely dramatically alter what the incoming Biden administration’s Middle East policy will look like.

The enmity between the Jewish state and the Arab Islamic world is long and deep. Israel fought four wars with its neighbors between 1948 and 1973, and has engaged in continuing conflict with many Arab states ever since. Saudi Arabia and other Persian Gulf nations had participated in some of those wars, bankrolled Palestinian terrorist groups and refused to diplomatically recognize Israel. Even as Israel made peace with Egypt and Jordan, Saudi Arabia and its allies continued to consider peace with any Israeli government as unacceptable.

That has changed for the oldest of diplomatic reasons: self-interest. The Iranian regime views both Israel and the Sunni gulf kingdoms as illegitimate and has worked tirelessly to bring them down. Tehran also funds terrorist groups such as Hezbollah, and rebel groups such as those in Yemen, to put military pressure on Saudi Arabia and Israel. This alone brings these two together.

Iran’s attempt to bring Iraq fully under its sway particularly presents threats to the Saudis and the gulf kingdoms. Iraq shares extensive borders with Kuwait and Saudi Arabia. If Iranian-backed troops were ever stationed in the Shiite regions in southern Iraq, they could easily launch an invasion at a moment’s notice. Saudi Arabia’s Eastern Province, which is directly south of Kuwait, holds much of the kingdom’s oil wealth and Shiite population, and the oil-rich gulf kingdoms also all border the Eastern Province. It is crucial to Saudi and the gulf kingdoms’ security that Iranian forces be kept as far away as possible.

It is against this backdrop that Iran’s pursuit of a nuclear weapon must be understood. Were Iran ever to obtain such a weapon, its ballistic missile technology would put Israel and the Arabs alike at risk of nuclear blackmail. That in turn amplifies the conventional military power of Iran and its proxies. The Islamic republic could launch invasions or incursions as it pleases, secure in the knowledge that its nuclear weapons would deter serious retaliation.

Changes in U.S. policy during the Obama administration sent shock waves into the region. Both Israel, which is believed to possess its own nuclear deterrent, and the Arab kingdoms had long relied on the United States to protect them against Iranian subversion. The Iran nuclear agreement clearly called that implicit guarantee into question. For the Israelis, it meant that they could no longer be sure that U.S. troops would be deployed to assist them in a crisis. For the gulf kingdoms, it meant they needed a firm, nuclear-armed ally whose commitment to opposing Iran was unquestioned.

The recent dramatic changes in Arab policy toward Israel make sense when viewed in this light. For Israel, an alliance with the Arab gulf powers provides military might that could be deployed on its behalf in the event of a mutual threat. It also provides, in theory, geographic proximity to Iran to launch any secret incursions that U.S. ships or bases might currently provide. For the Arabs, it ensures that a nuclear-armed power stands behind them should Iran ever obtain a weapon, and establishes a connection with Israel’s vaunted intelligence agencies. A de facto alliance would also reduce dependence on the United States and its domestic political whims, replacing U.S. mediation with direct ties between the nations’ security apparatuses. Abandoning the Palestinians in the face of such concrete advantages is, if artfully done, obviously in the security interest of the Saudis and gulf kingdoms.

The national security appointments President-elect Joe Biden announced Monday are not likely to give either side more comfort. John F. Kerry, who will serve as Biden’s climate envoy, was secretary of state when the Iranian nuclear accord was signed, and was part of the Obama administration’s not-so-subtle opposition to Netanyahu in the 2015 Israeli election. The incoming director of national intelligence, Avril D. Haines, signed a letter calling on the Democratic Party to revise its draft 2020 platform language on Israel to make it more vocally opposed to Netanyahu’s stated goals regarding the West Bank and Palestinian statehood.

Israel and the Arab kingdoms know that Iran means to destroy them. As writer Samuel Johnson once put it, impending death “concentrates [the] mind wonderfully.” The Biden administration is likely to find that this alliance of strange bedfellows will force its Middle East policy to look much more like the Trump administration’s than any of them currently imagine.

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