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In 1986, Senator Joe Biden gave an impassioned pro-Israel speech that was broadcast to the American nation.
“Were there not an Israel, the United States of America would have to invent an Israel to protect her interests in the region,” he shouted, waving his arms to emphasise his point.
“It is the best $3 billion investment we make.”
Almost 40 years on, Mr Biden, who now holds the ultimate authority over this special relationship, remains a staunch backer of Israel. On Wednesday, he told journalists that US support of Israel is “ironclad”.
Today, his support for Israel faces more challenges than in 1986.
The US continues to provide vast amounts of financial support to Israel, giving almost $4 billion in 2023, the vast majority of which was military aid.
But Mr Biden is under growing pressure to defer or even halt arms transfers to Israel, which has been accused of committing war crimes during its continuing operation in Gaza.
Many of Mr Biden's fellow Democrats have questioned both the return and the ethics of the US' massive investment in Israel.
Democrat senator Bernie Sanders told CNN on Wednesday that “not another nickel” should go to Israel.
Many traditional Democratic voters say US military aid makes the country directly complicit in alleged Israeli war crimes, particularly in Gaza.
In Michigan, where many Arab-Americans live, more than 100,000 voters cast uncommitted Democratic ballots in the state's primary election in February, after a campaign centred on Mr Biden's support for Israel.
International support for Israel is also eroding, including among its traditional allies in Europe, as accusations of genocide take hold. Israel has faced a genocide case at the International Court of Justice, and recently a UN report found Israel's actions in Gaza met several of the criteria listed in the Genocide Convention.
Amid this mounting pressure, Mr Biden will also be aware that Israel faces critical threats that it may need American support to withstand.
The country is on high alert ahead of an expected Iranian retaliation for the attack on Iran's embassy in Damascus. The attack could be direct or come via one of Iran's proxy groups such as Hezbollah, which possesses a large arsenal of missiles capable of striking Israeli territory, or the Houthi rebels in Yemen, who have launched attacks at the Israeli port city of Eilat.
Tensions are also seething in the occupied West Bank, where the risk of a mass uprising by Palestinians remains.
Israeli military officials and experts are confident they can deal with this dangerous situation, as long as US military aid keeps coming.
Israel researcher Yoel Guzansky said the American voices talking critically about arms exports to Israel are a “worrying new development”, but that the administration will still draw a distinction between Israel’s conduct in Gaza and its defence against Iran.
“The president has said he will defend Israel against Iran and its proxies no matter what. I think he will. The voices [critical of] arms exports to Israel are worrying. It’s a new development, but they are two separate things,” Mr Guzansky told The National.
The US is still on course to deliver vital military aid to Israel.
Washington is preparing to approve another arms transfer to Israel that could include 50 F-15 fighter bombers. Already approved and in the pipeline of supplies is a package of 25 F-35 fighter jets, and 1,800 2,000-pound bombs.
The latter has caused widespread alarm among conflict monitors, who say that Israel's use of massive bombs such as these has caused mass civilian casualties.
Other pending arms transfers include 24,000 assault rifles and Joint Direct Attack Munition kits, which are used to change unguided bombs – of which Israel has a vast stockpile – into guided bombs.
All of these weapons could be used in Gaza and on Israel’s borders with Lebanon and Syria, but there is also equipment that could be used in a major confrontation with Iran.
Critically, they include the F-15EX, which can almost reach Iran without refuelling, and KC-46A aerial refuelling tankers, state of the art aircraft that would allow a large Israeli aerial armada to bombard Iran in the event of war. Without the tankers, US backers of Israel say its ability to defend itself against Iran will remain limited.
All expectations point to these deliveries being made.
Israeli security expert Orna Mizrahi said that the US is “still obligated to defend Israel despite the tactical differences with the Israeli government”.
“Therefore the understanding is that no American embargo on arms transfers is expected at least until the US elections,” she added.
But when Mr Biden makes impassioned speeches vowing “ironclad” support of Israel today, he does so facing an American political establishment and public that is far more sceptical than it has ever been about the wisdom of his words.
