Accordingly, if the United States unilaterally sabotages the agreement or forces an Iranian withdrawal, it will only exacerbate the current situation beyond salvageable means. During the JCPOA negotiations, Iran made its consent contingent upon having the “right to enrich” uranium, ensuring that the outcome of any subsequent negotiations will require the same. Additionally, since the unity of the international community post-American decertification is suspect, it will be exceedingly difficult to garner the economic and political pressure necessary to force Iran back to the negotiating table. Consequently, an American withdrawal will only release Iran, now empowered by sanctions relief, from its political commitments and set it towards attaining a breakout capability.

If Iran begins approaching a nuclear weapon, then the United States will find itself in another Korean crisis, with action and inaction both incurring unacceptable costs. Although there is no equivalent to Pyongyang’s ability to hold Seoul at risk, Tehran can threaten America’s security interests through a variety of conventional and asymmetric means. For instance, Iran can abruptly inflate oil prices by harassing or blockading international shipping in the strategic Persian Gulf and narrow Strait of Hormuz via the placement of undersea mines, artillery, ballistic missiles and midget submarines. Likewise, the Iranian IRGC has honed capabilities which are specifically designed to offset the United States’ conventional and technological supremacy. Anthony Cordesman of the Center of Strategic and International Studies has detailed how IRGC cells at the battalion and squad level have been trained to fight conventionally and irregularly or to direct proxy forces against American regional assets despite the loss of Iranian command, control, communications and intelligence capabilities. Nevertheless, limited military action cannot erase Iran’s technical ability nor its propensity to pursue nuclear weapons to ensure regime survival, leaving regime change as the only viable, albeit costly, means to decisively prevent an Iranian nuclear weapon.

These military threats will likely worsen with the extension of the Russian-Iranian alliance, which has deepened since Russia entered the Syrian Civil War (SCW) in 2015. In Syria, Russia has fought from the air in support of Iranian ground forces, creating a symbiotic relationship where the IRGC and its proxies would supply intelligence for Russian airstrikes. That Russia has established a joint operations center in Baghdad with Iran and Syria to share information in the fight against the Islamic State speaks to the transnational nature of the rising Russian-Iranian relationship. Even though Russia and Iran do not always share the same strategic objectives, both nations relish opportunities to undermine American influence in the Middle East, and both are benefitting from bilateral military cooperation and arms deals. For instance, Iran recently spent $800 million to obtain the Russian S-300 surface-to-air missile system and, according to Russian officials, may purchase another $10 billion in arms once limits on Iranian offensive weapons purchases expire in 2020.

Russia has also hosted Iranian Maj. Gen. Qassem Soleimani, the leader of the IRGC’s extraterritorial and elite Quds Force, three times over the past three years in violations of UNSC sanctions. Considering that Soleimani has direct control over Iran’s regional proxy forces, his frequent visits to Moscow are particularly unnerving. Reports of direct cooperation between senior Russian and Lebanese Hezbollah military personnel at operations rooms in Latakia and Damascus, and Russian special operations forces wearing Hezbollah insignia in Syria, do little to assuage these concerns. Previously, IDF Brig. Gen, Muni Katz and Nadav Pollak revealed at the Washington Institute that Hezbollah has gained exposure to Russian military thinking, intelligence analysis and planning as well as indispensable experience in complex offensive operations. As the authors warn, “this will be the first time [Hezbollah] will be able to watch how a first-tier military plans a fighting campaign.”

The Russian-Iranian alliance also has implications for the United States’ Middle Eastern strategy outside of Iran. While Russia has been careful to not needlessly antagonize the Israeli national-security establishment in Syria, it has seemingly stood by as Iranian efforts to empower Hezbollah have progressed. Despite that Israeli prime minister Benjamin Netanyahu had personally visited Russian president Vladimir Putin four times since last summer, Moscow has thus far been unwilling to push back on aggressive Iranian overtures in both Syria and Lebanon—with the most recent being the production of missile facilities in both countries. If Iran continues to defy Israeli red lines in Syria and Lebanon, then it is likely that the pace of Israeli cross-border operations will increase and disrupt American-backed ceasefires in Syria, which Jerusalem views as supportive of Iran’s goals.

Over time, Israel’s reaction to the JCPOA has progressively shifted between severe anxiety and measured reticence. Originally, Netanyahu had decried the deal as a “stunning historic mistake” because, because he saw it as a temporary agreement that provided legitimacy to Iran’s nuclear program. Yet, notwithstanding the Israeli national-security establishment’s enduring belief in Iranian malevolence, the deal faded from the political limelight as more immediate threats stemming from the SCW and Palestinians captured the public’s attention. Since then, Israel has primarily sought to monitor Iranian compliance within the scope of the deal, but its officials have often been unable to avoid disparaging its tenets. For example, while speaking on September 11 at an anti-terrorism conference, Israeli intelligence minister Yisrael Katz urged President Trump to renegotiate or withdraw from the deal as it “protects Iran’s ability to get nuclear capabilities in the future.” However, Carmi Gillion, a previous director of Israel’s General Security Service (the Shin Bet), argued in July for Foreign Policy that the JCPOA has not been all bad for Israel. By examining the regional security environment, Gillon found that the JCPOA has achieved laudable successes, such as dismantling the majority of Iran’s nuclear infrastructure and increasing its breakout time. A nuclear-capable Iran, Gillion says, would pose the apex existential threat to Israeli security and complicate Israeli and American policy options in addressing Iran’s malign activities. Gillon believes that the agreement has provided Washington and Jerusalem with time to develop a counterstrategy, when before time was of the essence.

Iran’s other neighbors have had more varied responses to the JCPOA, from unease to utter displeasure, but have accepted the agreement as it stands. Of all the states disturbed by an Iranian nuclear weapon, none has been so public in its intentions as Saudi Arabia, which remains mired a struggle with Iran for religious and regional hegemony. Although the Saudis are currently a party to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), there is evidence that Saudi Arabia would develop nuclear weapons in parallel to Iran. For instance, a 2008 report to the U.S. Senate Foreign Relations Committee noted that states often choose to “dial up or dial down” their programs to “keep their options open” and that Washington cannot take Riyadh’s commitment to nonproliferation for granted. To drive this point further, BBC correspondent Mark Urban reported in 2013 that King Abdullah, the previous Saudi monarch, confirmed to Dennis Ross that Saudi Arabia would pursue whatever nuclear capability Iran achieved, including nuclear arms. In the medium- to long-term interim, Saudi Arabia’s technical shortcomings are insufficient to prevent the kingdom from developing a latent breakout capability given that Riyadh is pursuing a nuclear energy development as well as building the scientific and industrial base for a nuclear hedge.

In comparison to Saudi Arabia, Turkey and Egypt have responded with greater political restraint. Both countries have found Iran’s growing regional influence disconcerting, despite that Ankara and Cairo have found themselves on different sides in the SCW. Iran and Turkey have shared an uneasy balance of power for decades, but that has been threatened by the former’s nuclear aspirations, extensive proxy forces and conventional buildup brought on by sanctions relief. On September 12, Turkish president Erdogan gave a nuanced statement on the consequences of “Persian expansionism” that also mentioned how Iranian efforts were crucial to stabilizing Iraq and Syria. Turkey remains a low proliferation risk in the near term, due to its privileged position as a NATO member and a beneficiary of the American nuclear security umbrella. Therefore, Ankara has an interest in seeing the JCPOA’s continued implementation, not only to suppress the impetus for regional proliferation by keeping Iran out of the nuclear club, but also because sanctions relief serves to grow its bilateral trade with Tehran.

For his part, Egyptian president Abdel Fattah el-Sisi has avoided military involvement in the region’s tumultuous events, instead trying to foster internal stability at home and fighting ISIS in Sinai. As a secular military leader who came to power by ousting an Islamist government, Sisi has preferred stability and backed strongmen like Syria’s Bashar al-Assad over the chaotic forces that he sees engulfing the region. When the JCPOA was signed, Egypt accepted the outcome, but was forthcoming in its intention for reassessment if Iran reneged on its promises. As a leading member of the international Non-Aligned Movement, Egypt has long rallied for nuclear disarmament internationally and sought a weapons of mass destruction free zone in the Middle East. Consequently, Egypt’s primarily interest is in the JCPOA succeeding, which is something that Egyptian Ambassador to the UN Amr Abdellatif Aboulatta emphasized to the Security Council in January. Nonetheless, that Aboulatta has also condemned Iranian regional arms trafficking as well as Tehran’s “interference in the affairs of Arab states” speaks to the growing Arab unease pertaining to Iran’s growing influence in its backyard.