(CNN) US President Joe Biden and Israeli Prime Minister Benjamin Netanyahu have been friends, allies and partners in a relationship that has spanned nearly four decades. When they first met, Biden was a junior senator in his early 40s; Netanyahu was a fledgling diplomat nearly a decade younger. Now with their first phone call expected imminently, the two must decide how their relationship will evolve, at the height of their careers and the peak of their powers.
But the last four years will complicate the next four with Biden's desire to eventually reenter the Iran nuclear deal and his choice of former top-level Obama officials who crafted and advocated for it, a likely early flash point.
Netanyahu was a bottomless source of unwavering support for Donald Trump in office, not once publicly criticizing the unpredictable and often spiteful President. The 71-year-old celebrated nearly every foreign policy initiative of the Trump administration in the Middle East, becoming his most visible international cheerleader.
With an upcoming election, a third national lockdown, and an imminent resumption of his trial on corruption charges, Israel's longest-serving leader must work with the man who ousted Trump from the Oval Office.
Biden's relationship with Israel stretches back nearly a half-century to when he met then-Prime Minister Golda Meir in 1973 as a freshman senator from Delaware. Since then, it has grown into a "very emotional attachment to Israel," one former Obama administration official told CNN. "He sees Israel through that lens and as a genuine democracy in a region not characterized as that."
Biden and Netanyahu first developed their friendship in the 1980s, when Biden was a young senator serving on the Foreign Relations Committee and Netanyahu was serving in the Israeli embassy in Washington, DC. Over the years, the two men got to know each other, met each other's families, and kept in contact as Netanyahu rose through politics to become Israel's prime minister in 1996.
When Netanyahu lost his election to Ehud Barak three years later, "Biden stayed in touch with him, wrote him an occasional note, things politicians wouldn't ordinarily do," said a source familiar with the relationship. "I know Bibi appreciated it. Biden didn't treat him like a has-been." As the years went by, Netanyahu would stop by Biden's office to visit on his trips to Washington.
But the friendship was tested once Biden became vice president to Barack Obama. Netanyahu infamously lectured Obama on Middle East politics in the White House in 2011, then featured it in his election campaign in 2019.
When Biden visited Israel in 2010, Netanyahu's government announced new settlement building in East Jerusalem, which then-Secretary of State Hillary Clinton called "insulting."
"The later years of the Obama administration were tough. Some of the team will remember that, but [Biden is] not going to have any interest in stoking the tensions," said one source familiar with the relationship. Netanyahu clashed with Obama over negotiations with the Palestinians, then again more openly over the Iran nuclear deal.
Despite the friction, the personal relationship between Netanyahu and Biden persevered. In 2014, Biden said he once told Netanyahu, "Bibi, I don't agree with a damn thing you say, but I love you." Biden's friendship with the brash Israeli leader was seen as an asset during the Obama presidency, and Biden was thought of as the one who could smooth things out, according to sources familiar with the dynamics.
But the dynamics have changed.
Netanyahu long ago became a political chameleon, shifting from the Prime Minister who endorsed a two-state solution to the Israeli-Palestinian conflict in an important speech in 2009 to the leader who endorsed Trump's vision for Middle East peace a decade later, which discarded any conventional notion of two states for two peoples. He has led centrist, center-right, and right-wing governments in his 14 years in office but no period was as good for him -- or as easy for him -- as the Trump administration. Trump was Netanyahu's gift that kept on giving.
Before the first of three elections in a year in April 2019, Trump recognized Israeli sovereignty in the Golan Heights and declared Iran's Revolutionary Guard Corps a terrorist organization, a move for which Netanyahu claimed partial credit. Before the third straight election in March 2020, Trump unveiled his plan for Middle East peace, standing next to a beaming Netanyahu, who explained most of the details of the plan himself.
In exchange, Netanyahu appeared to align Israel ever more closely with the Republican Party, even going so far as to name a new settlement in the Golan Heights after the former President, called Trump Heights. When Netanyahu joined Trump at the White House for the signing of the Abraham Accords alongside the Emirati and Bahraini Foreign Ministers, the Israeli leader did not meet with any Democratic politicians.
Ron Dermer, Israeli Ambassador to the US and one of those closest to Netanyahu, was a frequent visitor to the White House. Dermer's term ended the day the Biden administration took office.
Israeli Minister Tzachi Hanegbi insists Netanyahu's policies were never pro-Republican or pro-Democrat, but aligned only with Israel's needs.
"Our policy is always bipartisan," Hanegbi said, "but of course [Netanyahu] was always very satisfied with the policies from Trump."
"When we will have a great relationship with the Biden administration -- and we will have a great relationship with the new administration -- it doesn't mean we are pro-Democratic and anti-Republican," he said. "The chemistry, the intimacy, the mutual recognition of each other's passion for his country -- these are things that can create credibility to each other's policies."
But Netanyahu is now in the midst of a fourth election campaign in two years, with no guarantee that the country can break the cycle of endless elections. Netanyahu benefited politically from attacking Obama, showing the Israeli public that he had the fortitude to stand up to an American leader. Now he must decide whether to do so under Biden.
"Netanyahu is a supreme diplomat, but when it came to the US, he carries the burden of his almost explicit allegiance to the GOP," said Dani Dayan, Israel's former New York Consul-General and a candidate for the New Hope party, challenging Netanyahu's Likud in the March 23rd election. "Israel's next prime minister will have much to do to restore the bipartisan relationship."
Netanyahu is under attack from Gideon Sa'ar, an ideological right-wing politician who split from Netanyahu's Likud party to form the New Hope party. Despite Sa'ar's opposition to territorial concessions and a two-state solution, he has vowed to restore bipartisan support of Israel, positioning himself to be a better partner for Biden.
"I will rebuild Israel's good and balanced relationships with both sides," promised Sa'ar in a Zoom meeting with AIPAC. "As Prime Minister, I will work with President Biden and his administration to stress the importance of not returning to the previous deal."
Biden has a strong belief in foreign policy built, in part, on personal relationships, analysts told CNN, but his friendship with Netanyahu will likely be tested by political pressure in the months to come. The election is only one challenge, and it may not even be the first one with the potential to strain the relationship.
The Biden administration's direction on a nuclear deal with Iran is at the top of the priority list for Israel. The original nuclear deal was the source of some of the most bitter disputes between Obama and Netanyahu, highlighted in the Prime Minister's decision to speak before a joint session of Congress in 2015, a speech which Obama did not attend.
"Israel's relations with Obama were frosty, they got off to a bad start and never recovered," said David Makovsky, a director at the Washington Institute for Near East Studies. "But Biden is someone Israelis know. He's been around for a longtime."
Tony Blinken, Biden's newly confirmed Secretary of State, has said the administration would not roll back American recognition of Jerusalem as the capital of Israel or return the embassy from Jerusalem to Tel Aviv. Yet Biden's press secretary, Jen Psaki, said Biden viewed a two-state solution as the only path forward to resolve the Israeli-Palestinian conflict, and Biden is expected to pursue at least a reduction in settlement expansion in the West Bank, especially following the surge of approvals under the Trump administration.
Even so, Biden is not expected to put Israeli-Palestinian negotiations very high on his agenda, according to one former Obama official who worked on the region, who said the administration "does not want to spend the political capital" on the issue.
"With Biden, there won't be this perception that he is out to get [Netanyahu]," said veteran diplomat Dennis Ross, who served as a Middle East negotiator and adviser to three US administrations.
"That's not what this relationship would be," Ross added. "There was a perception that grew up in Israel that Obama wasn't fair to Israel. Standing up to an American president who doesn't look fair is seen as a good thing in Israel. Standing up to an American president who is seen as fair isn't great. Biden is largely seen as being fair."