In the longstanding U.S.-Israel alliance, the former has always been regarded as the more senior partner. The U.S., after all, is an economic and military powerhouse. It’s the biggest supplier of military aid to Israel, providing $3.8 billion in assistance per year. It also acts as Israel’s chief defender at international forums such as the U.N. Security Council, where Washington routinely uses its veto power to block resolutions critical of Israel.

While this dynamic has earned the U.S. the designation of being Israel’s closest ally, it hasn’t always worked to its own interests in the region. Growing frustration within the Biden administration over the Israeli government’s handling of its months-long war to root out Hamas from Gaza has spilled into public view in recent weeks, with reports of President Biden privately referring to his Israeli counterpart Prime Minister Benjamin Netanyahu as an “asshole” whose handling of the war he has been publicly derided as being “over the top.” 

But despite Washington’s considerable leverage on Israel, the Biden administration has so far proven itself seemingly unable, or unwilling, to wield it—a reality that hasn’t gone unnoticed at home or abroad. Calls to introduce conditions on U.S. aid to Israel have grown within Congress. Some U.S. allies have urged Washington to do the same.

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“When the United States of America stands up and says something publicly, it matters,” State Department Spokesperson Matthew Miller told reporters on Monday in response to a question by the Associated Press’s Matt Lee, who asked how the U.S. has used its leverage beyond simply “wagging its finger.” “We have seen the government of Israel respond to it—not always in the way we want, not always to the degree or the level that we want,” Miller continued.“But our interventions, we believe, have had an impact.”

That hasn’t always borne out. Public pronouncements by U.S. officials about the humanitarian crisis in Gaza (which Blinken referenced when he told Israeli leaders that Hamas’s deadly Oct. 7th attack “cannot be a license to dehumanize others”) or the mounting civilian death toll (Biden warned Israel against going forward with its planned invasion of Gaza’s southernmost city of Rafah absent a “credible and executable plan” for protecting the Palestinian population sheltering there) haven’t been met with notable shifts in Israel’s strategy. And while the administration has pointed to an increase in humanitarian aid as evidence of its impact, critics argue that it isn’t nearly enough to meet the needs of the enclave as it faces mass starvation. Indeed, an effort as seemingly straightforward as securing the delivery of a U.S.-funded flour shipment to Gaza—a commitment that Netanyahu reportedly made to Biden personally—was ultimately scuppered by Netanyahu’s ultranationalist coalition partners. 

“It is frankly preposterous that we are haggling over bags of flour,” says Matt Duss, the executive vice president of the Center for International Policy and a former chief foreign policy advisor to Sen. Bernie Sanders, one of the most vocal proponents of conditioning U.S. aid to Israel. “This is not something the United States should have to haggle with a small partner state like Israel over considering the enormous amount of support that we give them and the enormous reliance on us that they have.”

Longtime observers of Biden say his apparent deference to his Israeli counterpart is a feature, not a bug, of his approach to U.S.-Israel relations. Unlike his former boss President Obama, who openly sparred with Netanyahu over Israeli settlement expansion and its implications for U.S.-led peace efforts, Biden has long been unwavering in his support for Israel and its government, even going so far as to cultivate a reputation for doing more than any other Obama administration official to shield the Israeli leader from diplomatic pressure. As president, Biden has largely continued with that approach—one that is informed as much by his longstanding affinity for Israel as it is by his own agreeable political style.

“He was never the kind of guy who likes to air his disagreements in public,” says Jonah Blank, a former foreign policy advisor to Biden during his time in the Senate. “He feels like you’re much more effective if you are publicly as cordial as you can be and deliver the tough news in private..”

While the Biden administration argues that this approach has reaped some results in terms of increasing humanitarian assistance and reducing civilian casualties, it has also conceded that they have not been enough. “I will say I think that sometimes people pretend that the United States of America has a magic wand that it can wave to make any situation in the world roll out in exactly the way that we would want it to and that is never the case,” Miller, the State Department spokesperson, said during Monday’s press conference. But some reporters countered: If billions of dollars in military aid isn’t a magic wand, what is?

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The perception the U.S. isn’t using the levers it has at its disposal stands to have profound consequences not only for Gaza (where more than 28,000 Palestinians have been killed and millions internally displaced), but for U.S.’s foreign policy interests writ large. “We’re having this conversation about how horrible it would be for U.S. credibility and U.S. leadership if we fail to support Ukraine,” says Duss, referencing Congressional Republicans stalling billions of dollars in vital U.S. aid to Ukraine. “The same applies here. Our inability to exert any meaningful influence on Israel—a state that is hugely reliant on U.S. support—is also enormously damaging.”

That damage risks extending to Biden personally as he embarks on his reelection campaign. The president is already seen to have lost substantial support among Arab American and young progressive voters over his handling of the Gaza war, which some observers warn could cost him support in key swing states. While the administration has taken some steps to address these concerns—among them a recent executive order designed to punish rising Israeli settler violence against Palestinians in the occupied West Bank and a new memorandum requiring allies who receive U.S. military aid to provide “credible and reliable written assurances” of their adherence to international law—neither are expected to have a tangible impact on the war in the short-term. Their long-term impact will depend on how, or if, Biden chooses to use them.

“The tools are there,” says Blank. “Could they actually be implemented in the course of the few months that we have before the November election? … Right now, what President Biden is looking at is the sands running out domestically quicker than he is responding to the challenge.”