In his quest to discover the sources of the growing rift between American Jewry and Israel, Daniel Gordis convincingly argues that, rather than being traceable to the character of Israeli policy vis-à-vis the Palestinians, or to changing patterns in American Jewish life, the rift is over issues of “moral and political essence and ideology”—issues of, in a word, identity. He proceeds to diagnose four divergent “political and cultural assumptions” that, taken together, expose the ways in which Israel and America represent “two fundamentally different if not antithetical political projects.” Although the resultant tensions between Israeli and American Jews are “as old as Israel itself,” rarely if ever have they generated the fissures currently dividing the two communities. The question, then, is: why now?

In what follows, I mean to expand on the reasons advanced by Gordis with some background reminders from American political history. This history shows that inter-communal tensions are not the only or even the most important factors in the rift. Although, as Gordis notes, suspicion and misunderstanding plagued relations between American Jews and the Jewish state from Israel’s inception, they were also tied in great part to a tension that pervaded U.S.-Israel ties more broadly, and that has its locus in the shifting priorities of American foreign policy.

In May 1948, President Harry Truman swiftly extended diplomatic recognition to the newly born state of Israel. Nevertheless, during its War of Independence, he also imposed an arms embargo that imperiled Israel’s ability to repel invading Arab armies. For his part, Truman’s successor Dwight Eisenhower at first distanced America from Israel as he sought to win over Gamal Abdel Nasser and convert the Egyptian dictator’s influence into coin on the Arab street more generally. His administration even established a CIA front group to counteract popular American sympathy for Zionism.

Although the relationship improved somewhat under the Kennedy administration, it remained tepid until the Six-Day War. Just as Jerusalem’s stunning success in that conflict “did much,” as Gordis writes, “to soften feelings” toward Israel among American Jews, more significantly it did the same in Washington. Israel’s victory demonstrated the logic of a U.S.-Israel alliance. Morally, the Jewish state represented at once a fellow democracy in a region otherwise devoid of free societies and a plucky underdog pursuing its national self-determination in the mold of America’s founding fathers. Strategically, Israel could serve as America’s battleship in the Middle East; armed with U.S. weapons, it could help balance and beat back Soviet power.

The new partnership quickly took hold. President Lyndon Johnson began to speak of the Jewish state with the moral conviction that would become common among later presidents. Soon after the war, when the Soviet premier Aleksei Kosygin asked why the U.S. would back a country with only three million citizens against 80 million Arabs, Johnson responded: “because it is right.” Many Americans appeared to agree. In June 1967, a Gallup poll had found 38 percent sympathizing more with Israel than with the Arab nations; by January 1969, that number had jumped to 50 percent.

Throughout the 1970s and the early 1980s—despite Arab oil embargoes, despite the humiliation of the American defeat in Vietnam and the ensuing years of foreign-policy confusion and disillusionment—Israel successfully reinforced its moral alignment with the United States. It did so through its performance as the forward arsenal of American might in the Middle East. As I’ve recounted elsewhere, Israel saved the U.S.-backed Hashemite kingdom in Jordan from a Syrian invasion, humiliated the Soviet Union by downing its planes over the Suez Canal, and opened the port of Haifa to the U.S. Sixth Fleet to counter the Soviet presence in Syria. Most spectacularly, in the summer of 1982, Israeli pilots flying U.S. planes downed 86 Syrian-manned Soviet MiGs without suffering a single loss.

Israel’s achievements generated American goodwill. When asked in the 1970s whether a so-called Jewish lobby was taking over Congress, Henry “Scoop” Jackson, the Democratic Senator from Washington, responded that Americans of all kinds, far from being in the thrall of lobbyists, “respect competence. They like that we are on the side which seems to know what it’s doing.” In 1988, 63 percent of Americans averred to pollsters that an “extremely important” or “very important” reason for U.S. support of Israel was that the country was “the most outspoken foe of Communism in the Middle East and its strength prevents the Soviets from gaining even further influence in the region.”

American Jews, for their part, largely adhered to the same views. Not only did they remain strongly pro-Israel, but, as Gordis points out, they “saw no friction between those feelings and their feelings as proud Americans.” And this seamless support would persist, at least on the surface, throughout the Reagan presidency and until the collapse of the Soviet empire—after which the tectonic plates undergirding the U.S.-Israel alliance and, correspondingly, the American Jewish relationship with Israel began to shift.

In the decades immediately following the end of the cold war, polls found Americans increasingly eager to focus on domestic affairs and far less willing to send troops abroad. A string of foreign-policy frustrations reinforced that reluctance, from the Blackhawk Down debacle in Somalia to the persistent struggle with Saddam Hussein’s Iraq. By the early 2000s, narratives about Western colonial sins and American aggression filtered from the universities and other centers of progressive opinion into political discourse, especially following the 9/11 attacks and under the influence of Democratic opposition to the 2003 Iraq war.

In turn, progressives began to picture the U.S.-Israel relationship as the embodiment not of enduring and largely bipartisan American values but of bad old “hegemonic” habits, and thus in need of reform or retirement. If America and Israel once stood together—the former the global beacon of freedom, the latter its Middle Eastern outpost—Washington in this reading could no longer allow itself to be weighed down by the moral albatross of Israel’s treatment of the Palestinians.

Worse, many in the foreign-policy community came to see Israel as an actual strategic liability. Pro-Israel policies, some argued, fueled anti-Americanism in the Middle East; to help calm the region, the United States should adopt neutrality. In 2006, the academics Stephen Walt and John Mearsheimer co-authored “The Israel Lobby,” an essay and later book contending that Washington no longer gained any strategic value from its alliance with Jerusalem. Although some of the authors’ more incendiary statements were swiftly condemned, the core argument reflected and enhanced a certain conventional wisdom among elements of the foreign-policy establishment. Within a few months, the report of the Iraq Study Group, a body convened by President George W. Bush, would contend as if it were self-evident that U.S. success in Iraq, of all places, depended in part on reviving the Israel-Palestinian peace process.

One of the lead authors of that report was Ben Rhodes, who would go on to shape and articulate President Obama’s redefinition of America’s global strategy, a central plank of which was to carve out “daylight” between the U.S. and Israel. By the end of the Obama administration, 55 percent of Democrats agreed that Israel was a “burden” to the United States.

To be sure, many liberal Democrats, including Obama himself, claimed that their criticism of Israel and advocacy of political pressure on it issued from genuine friendship and concern for its security. But by now the progressive position was becoming integral to mainstream Democratic opinion. Back in 2001, the Pew Research Center had found 48 percent of liberal Democrats sympathetic with Israel as against 18 percent for the Palestinians; by 2016 the weight had dramatically reversed, with 40 percent sympathizing with the Palestinians versus 33 percent with Israel.

As among Democrats, so in the world of American Jews, most of whom remain committed to the Democratic party. In February 2008, then-candidate Barack Obama took aim at the consensus support for Israel by identifying it with a specific “strain within the pro-Israel community” that demanded an “unwavering pro-Likud approach”; in its stead, he called for “honest dialogue” and a more “nuanced” conversation. Two months later, a group of Jewish activists founded J Street, an organization that, with Obama’s ascension to the White House, would declare itself the new president’s “blocking back” within the Jewish community.

As the Obama administration began to define Israel predominantly through the prism of its conflict with the Palestinians, denunciations of “the occupation” became a rallying point for social-justice protests and initiatives on the nation’s campuses. In accordance with the doctrine of “intersectionality,” whereby all alleged systems of discrimination, oppression, and “privilege” are presumed to be interrelated, progressive groups in America today are expected to join as one in the fight against their putatively common enemies. In actuality these groups often pursue particular and sometimes competing aims—but they frequently unite against, specifically, Israel. In 2016, for example, the Black Lives Matter platform accused Israel of genocide and endorsed the Boycott, Divestment, and Sanctions (BDS) movement.

Over time, numbers of liberal and progressive Jews have themselves not only increasingly adopted elements of the new narrative but have also actively joined the fight on the ground. In this new ideological environment, an organization like Jewish Voice for Peace, which also endorses the BDS movement, has gained increased prominence. And If Not Now, composed mostly of young American Jews, has formed to demand that an “out-of-touch” U.S. Jewish establishment and “American Jewish institutions . . . end their support for the occupation.”

Relevant here is the generational shift noted by Gordis. As confirmed in the 2013 Pew survey, 40 percent of American Jews aged sixty-five or older feel “very attached” to Israel, but only 25 percent of Jews under thirty feel the same way. Similarly, Jews under thirty are significantly “less apt to say Israel is making sincere efforts at peacemaking” than are older Jews. Both results—and notably the second, in which the burden of blame is laid squarely on Israel—reflect the post-cold-war shift in attitudes toward America and to its foreign policy within centers of opinion commanding the sympathies of many younger Jews.

None of this is to deny that cultural, religious, and demographic trends within the American Jewish community itself, as well as aspects of Israeli foreign and domestic policy, have affected the deteriorating relationship between U.S. Jews and Israel. At the same time, more is going on in American politics, including as it relates to Israel, than the march of progressivism.

For one thing, even as Democratic sympathy for Israel has plummeted, Republican sympathy has skyrocketed, from 50 percent in 2001 to 74 percent by 2016. For another, as recent events in the Middle East once again demonstrate, the traditional and deep-seated moral and strategic alignment between America and Israel, and between the American people and Israel, still very much exists. This enduring alignment is very much at odds with the predilections and convictions of progressives who no longer subscribe to the values that underlay and still infuse it—and should itself be seen as a key factor exacerbating the underlying divisions between American Jews and Israel that Daniel Gordis incisively documents.