“There must be no return to the previous nuclear agreement. We must stick to an uncompromising policy to ensure that Iran does not develop nuclear weapons,” Israeli Prime Minister Benjamin Netanyahu declared in a prepared speech shortly after the November elections in the United States.

Israel appears to be ratcheting up further pressure on the Biden administration by implicitly threatening military action against Iran should the administration rejoin the Iran nuclear deal, formally known as the Joint Comprehensive Plan of Action or JCPOA. Israeli army chief of staff Lieutenant General Aviv Kochavi — who saw value in the JCPOA in 2015 — escalated the current rhetoric substantially, telling a conference just this week, "If the 2015 nuclear deal had materialized, Iran would have gotten itself a bomb. … Anything resembling the current agreement is bad and must not be permitted.”

Kochavi’s remarks came against the background of the Israeli army’s request for substantial new funding to prepare operational military plans for possible use against Iran at a cost of $1.223 billion, on top of previous additional requests for $917 million and $764 million.

So is Israel serious about striking Iran anytime soon; and will those threats slow down or even dissuade President Biden from his preferred strategy, which is to reenter the JCPOA and only then begin to negotiate a longer and stronger agreement that takes into account Israel’s concerns? There is reporting that suggests Netanyahu really does not want a fight with Biden, whom he has known for decades, but prefers to try to coordinate U.S. and Israeli policies.

If that is the case, why has there been a spike in rhetoric and threats? Part of Netanyahu’s calculation is surely political. Israelis will go to the polls again in late March, and Netanyahu is fighting on several fronts to stay in power. His most vexing threat is the continuing COVID-19 crisis and resulting economic slowdown, especially in the tourism sector.

Netanyahu has gotten high marks for the swift rollout of Israel’s vaccination program, but prolonged mandatory lockdowns have cost him some support. Netanyahu will also be in court within weeks, facing indictments for corruption, breach of trust, and fraud. Thus, diverting the Israeli public’s attention away from these issues and focusing on Iran and security — Netanyahu’s strong suit among the Israeli public — could be smart election politics.

Netanyahu is also calculating that his new Arab allies in the Gulf — Saudi Arabia, the United Arab Emirates, and Bahrain — will boost his position in pushing back against American plans to restart negotiations with Iran. Israeli and UAE think tank experts are making the case jointly against a U.S. return to the JCPOA. The Saudis and the Emiratis are spending lavishly in Washington to get the message across.

Still, Netanyahu needs to be careful. Picking a fight with a popular U.S. president so soon after the inauguration is risky. Joe Biden — preternaturally pro-Israel for decades — isn’t Barack Obama, who was an easier target to attack. And then there’s Netanyahu’s track record. His feud with Obama, which Biden experienced up close for eight years, cost Netanyahu support among Democrats who have not forgotten his treatment of the popular former president and who now constitute a majority in both houses of Congress. Netanyahu likely considers that his initial willingness to deal with Obama’s demand in 2009 for a settlement freeze was a mistake. Better to come out swinging and avoid unwelcome initiatives from Washington from the outset.

Netanyahu might also calculate that Biden’s domestic and foreign policy agenda is so challenging that the president will yield to Netanyahu in order to avoid a U.S.-Israeli fight. It may not be a bad bet. With a slight edge in the Senate, a slim majority in the House, and midterms in less than two years, Democratic Party discipline will be hard to sustain.

Still, Biden and his national security team have been upfront in support of rejoining the JCPOA. They have also noted that it may take some time before re-entry to the JCPOA can be achieved; and they have promised to consult more closely with Israel and the Gulf states than took place before the JCPOA was originally agreed.

Adding Kochavi’s threat of Israeli military action to the equation, a central issue is whether such an Israeli threat is credible, i.e., would Israel take unilateral action against Iran without at least a “yellow light” from Washington?

Israel has formidable military assets and power, and a sustained Israel campaign against Iranian targets would inflict substantial damage on Iran’s nuclear facilities, as well as its infrastructure. If Israel is given access to Saudi and Emirati airspace and even basing, the biggest operational risks that have deterred Israel from acting in the past might be seen as low enough to accept.

Such sustained military attacks would surely set back the Iranian program. But it would not prevent Iran from reconstituting it. Nor would it eliminate the possibility of a serious war with Hezbollah. The former concern has never been taken seriously by Israeli policy makers, and the latter might be welcomed by those seeking a pretext to deal decisively with Iran’s Lebanese ally.

The price tag of such an Israeli decision, however, would be very high, perhaps prohibitive. Iran would respond in a manner and timing of its own choosing — terrorism against soft Israeli and American targets, probably including Jewish targets around the world. Hezbollah could launch thousands of rockets from Lebanon into Israel, perhaps accompanied by thousands of rockets from Gaza fired by Hamas and Islamic Jihad.

Even if Israel acted alone initially, the action-reaction spiral following that first attack would inevitably draw in the United States, especially if Iran’s retaliation led to American casualties. However strong Israel’s support is in the United States, would it want to bear responsibility for more U.S. military engagement among a war-weary American public?

In his speech, Kochavi emphasized that 2021 is not 2015, implying that Israel’s concerns about Iran and Iran’s capabilities are more pronounced today. Unclear, however, is the degree of support that Netanyahu and Kochavi enjoy within the Israeli defense establishment for a campaign of threats against Iran (and against the United States) that could lead to hostilities.

Before the JCPOA was agreed, Netanyahu — widely perceived to be risk-averse — reportedly argued three times for an Israeli strike against Iran, but could not gain support from within Israel or in Washington for such action. It is not clear today that the cautious views of Israel’s defense establishment have changed substantially since 2015.

While the escalation in Israeli rhetoric and its threats to attack could be little more than a means of exerting pressure on the Biden administration, neither Washington nor Tehran can be certain that excessive threats will not give way to action. Unless the Israeli government prefers to take on the Biden administration at this early stage instead of trying to coordinate approaches to Iran and the JCPOA, it would be well advised to tone down the public rhetoric and threats and focus on old-fashioned but effective quiet diplomacy with Washington.