Mohsen Fakhrizadeh, widely viewed as Iran’s most important nuclear scientist and the key figure in its nuclear weapons effort, was killed last Friday in an attack that has been attributed to Israel. Fakhrizadeh was publicly identified by Prime Minister Netanyahu two years ago as a name to remember when he revealed the existence of the nuclear archives that the Mossad lifted from a Tehran warehouse, and Fakhrizadeh is the latest in a line of Iranian scientists and engineers who have met untimely deaths. Given the pending change in administrations in the U.S. and Joe Biden’s stated intention to return to the JCPOA, much of the post-assassination commentary has focused less on Fakhrizadeh and more on how his killing will impact U.S. policy and U.S.-Israel relations going forward.

One of the arguments that immediately emerged is that if Israel was indeed the party behind the Fakhrizadeh killing, the primary purpose was to sabotage any possibility of Biden returning to the JCPOA or negotiating a new deal. The logic behind this argument is that Fakhrizadeh’s assassination will empower Iranian hardliners at the expense of more pragmatic regime elements, and thus this was all cooked up in the wake of Biden’s victory in order to handcuff his dealmaking ability and that had Trump won a second term, the hit on Fakhrizadeh would not have happened.

While there is no way to definitively determine whether or not this is correct, it strikes me as highly implausible. For starters, surveilling a person under tight Iranian government protection and whom the regime had taken great pains to shield from outsiders, planning the operation to kill him, recruiting the people necessary to carry out the plan, and then successfully executing it is not something that happens on a whim. For this to be primarily about hampering Biden would mean that it was all done in a matter of a couple of weeks, which is functionally impossible. 

Second, making this all about the JCPOA ignores a long history of Israeli and joint American-Israeli operations to disrupt Iran’s nuclear ambitions, from killing nuclear scientists to the Stuxnet virus to the explosions earlier this year at Parchin and Natanz, and undoubtedly extending to other incidents that we don’t know about. It ignores cooperation between the U.S. and Israel on this front during the Obama administration and before the JCPOA was negotiated. It ignores the basic fact that Israel has done everything it can short of a strike on Iranian nuclear facilities to thwart Iran’s nuclear ambitions. It is certainly possible that killing Fakhrizadeh will make it more difficult for Biden to reenter the JCPOA and negotiate a follow-on agreement, as he has said he is determined to do, and it is also possible that turning up the heat on Tehran to an even hotter temperature will make it easier for him to execute his plan. Whatever the eventual outcome, positing this latest move as being first and foremost about Biden’s JCPOA ambitions ignores a long string of facts, and it is noteworthy that of all the people publicly arguing as such, Biden and his circle of advisers are not among this group.

What the Fakhrizadeh incident and the ensuing fallout does do, however, is serve as yet another reminder as to why the Iranian nuclear issue was such a sticking point between the U.S. and Israel under the Obama administration and is likely to be so again under the Biden administration. While the Trump administration and the Israeli government were on precisely the same page with regard to a strategy of maximum pressure on Iran, American and Israeli interests and threat perceptions with regard to Iran are different no matter who sits in the White House. A nuclear Iran is a serious problem for both countries, and the U.S. – which has spent decades combating nuclear proliferation – does not want to see a nuclear arms race break out in the Middle East. Neither country will abet a nuclear-armed Iran.

Where the real difference lies is in the perceived threat from Iran’s non-nuclear activities. Israel has spent the past half decade worrying first and foremost about Iran’s conventional capabilities and in particular its ballistic missiles. Israel’s hundreds of strikes on Iranian and Hizballah positions in Syria have been directed not at Iran’s nuclear program, but at missile factories and missile shipments. An Iranian foothold in Syria, Iranian missile sites in Iraq, Iranian proxies in Lebanon, and Iranian IRGC troops hunkered down on the Syrian side of the Golan Heights are the most proximate threats that Israel deals with and they are non-nuclear ones. An Iran with nuclear capability makes dealing with all of these other issues harder since it gives the regime a layer of defensive security that it cannot otherwise possess (which is, incidentally, why nuclear weapons are generally viewed by international relations theorists as defensive weapons rather than offensive ones). This is why while Israel had issues with the substance of the JCPOA’s nuclear elements, its more vociferous objections were that the agreement sunset the conventional arms embargo (a sunset that has already kicked in) and the ballistic missile ban. This also accounts for the close confluence between Israel and Arab states on Iran; the UAE is not overly worried that it will ever be on the wrong end of an Iranian nuke, but it is endlessly worried about Iranian conventional capabilities. Halting Iran’s nuclear ambitions will not put an end to attacks such as the drone and cruise missile strike on Saudi oil facilities in September of last year.

For the U.S., this calculus is not nearly as pressing. The U.S. certainly wants to contain Iranian regional ambitions, prevent attacks on regional allies, and end targeting of U.S. troops in Iraq and Syria by Iranian-backed militias. But Iranian missiles and troop deployments do not present a direct threat to the U.S. homeland and do not raise the prospects of a hot war between the American and Iranian militaries. The nuclear issue is the more pressing problem and the one that the U.S. is determined to solve, potentially with the tradeoff of enhancing the Iranian regime’s overall position. This is not only the case with Democratic administrations; reports that Trump wanted to pursue his own Iran deal in a second term match his public statements to the same effect, and his track record with regard to North Korea suggests that he would have been unwilling to scuttle a potential deal trained on Iran’s nuclear program unless it also involved a complete ban on Iranian ballistic missile research and production.

Limiting a regional conventional arms race is going to be extremely difficult, if not impossible. This is even more acute in the wake of Trump’s decision to sell 50 F-35s and 18 Reaper drones to the UAE, and whatever corresponding compensation in terms of weapons system was pledged to Israel in order to maintain its qualitative military edge. Enhanced Israeli and Emirati conventional capabilities are not going to make it any easier to push Iran on widening the scope of the JCPOA to limit its own conventional capabilities, which will make it even more unlikely that a new deal is able to cover Iranian non-nuclear arms in a way that fully satisfies concerns of Iran hawks at home or the Israeli government. The upshot of this is that negotiating a new deal would be difficult under any circumstance, and the Fakhrizadeh assassination does not change that fact. But JCPOA or not, Israel would have had plenty of reasons to want to remove him from the equation, and focusing on the JCPOA angle only misses the larger considerations and forces at work.