The other version of the relationship is one of deepening polarization in both countries: the rightwing Israeli government cozies up to US Republicans and pursues extreme policies, while American views of Israel are increasingly divided along partisan lines.

Israel wants to be judged on its thriving democracy and economy, for which it deserves real credit. But one cannot ignore Israel’s military occupation of the West Bank and blockade of Gaza where a combined almost 5 million Palestinians live. Government-supported settlements in the West Bank are expanding, slowly taking over Palestinian land in what appears to be a creeping annexation.

In America, views of the Israeli-Palestinian conflict are more partisan than they’ve been since 1978, according to one study, which revealed that 79% of Republicans say their sympathies lie more with Israel than with the Palestinians, while only 27% of Democrats are more sympathetic to Israel. Another study revealed that, while a large majority of Democrats see Israel as a strategic asset, 55% of Democrats also see Israel as a strategic burden, and 60% of Democrats believe the United States should impose sanctions or take serious action in response to Israeli settlements.

The political fight in the United States over the Iran nuclear deal illustrates the partisan divide. In 2015 there was a Democratic uproar when the Republicans invited the Israeli prime minister to speak to Congress in opposition to the Iran nuclear deal being pushed by a Democratic president. This growing link between Israeli and American rightwing parties was reinforced by Netanyahu’s recent presentation supposedly showing Iran’s previous nuclear ambitions, which was just days later referenced by Donald Trump as justification for violating the deal.

The same goes for the Israeli-Palestinian conflict. Trump is backing Netanyahu’s government with hardly a critical word of Israeli activity towards the Palestinians. The embassy move is a case in point – it gains nothing for the United States, makes it impossible for the Palestinians to view this administration as a neutral mediator for peace talks, and stoked violence.

Israel has genuine security concerns, and the second intifada left deep scars on the Israeli psyche. For Israelis who remember wondering each day if their children were going to be killed by a suicide bomber on the way to school, the occupation allows Israelis to keep the Palestinians out of sight and out of mind. This is no small part of the reason why rightwing parties promising security have run Israel for almost two decades now.

But Israel cannot remain a democracy in the long run while continuing to rule millions of Palestinians who do not have any say in their governance. As I stood in the settlement in Hebron next to a young Israeli soldier guarding Israeli settlers, it was clear that while Israel is good at solving short-term problems – say, protecting Israeli settlers – it is not good at figuring out long-term solutions, like preventing Israel from becoming a perpetual occupier.

As one Israeli journalist told me in response to a discussion of the myriad challenges facing Israel, “we’ll schlep through”. Surely, the US-Israel relationship will also schlep through – but what kind of relationship will it be?

On my trip, I repeatedly heard the claim that fewer American Jews support Israel because they are moving away from Judaism, not because of Israeli policies towards Palestinians. As an American Jew who strongly supports Israel, but not necessarily Israel’s policies, this deeply offended me. Instead of criticizing American Jews for how they choose to live their personal lives, Israelis should recognize that, whatever the reason, falling support for Israel among a younger generation of American Jews will fracture the US-Israel relationship.

Fueling the fire in America are radicals such as Sheldon Adelson, who funds the largest Israeli daily newspaper “Israel Today” to support a rightwing agenda, and who has offered to pay for the new US embassy in Jerusalem. The Trump administration chose Pastor Robert Jeffress as one of the speakers at the opening of the Jerusalem embassy – the same Jeffress who once said: “Mormonism, Islam, Judaism, Hinduism – they lead people to an eternity of separation from God in hell.”

There are no obvious perfect solutions. But if the United States and Israel don’t work together to confront longer-term trends, the relationship could become unrecognizable, with a hyper-partisan segment of America supporting an Israel that has lost much of its claim to democracy. And that would be devastating for both countries.

• Michael H Fuchs is a contributing opinion writer for the Guardian US. He is also a senior fellow at the Center for American Progress, and a former deputy assistant secretary of state for east Asian and Pacific affairs