Harvard International Relations professor Stephen Walt writes in Foreign Policy Mar. 21, 2024:
Biden’s critics assume that the United States has enormous leverage over this situation and that a firm word from the president—combined with threats to curtail or halt U.S. aid—would quickly force Israel to change course. That assumption deserves scrutiny, however, because weaker states often refuse to comply with U.S. demands, and, sometimes, they get away with it. Serbia rejected NATO demands at the Rambouillet conference in 1999; Iran and North Korea have endured sanctions for decades and remain defiant; Nicolás Maduro is still in power in Venezuela; and Bashar al-Assad still rules in Syria despite earlier U.S. insistence that he “must go.”
These leaders were able to defy U.S. pressure because they were not dependent on American support, and each believed they had more to lose by complying than by hanging tough. But close U.S. allies sometimes resist U.S. pressure, too, as Germany did when it kept building the Nord Stream 2 pipeline despite U.S. objections. Even highly dependent clients can be surprisingly stubborn: Afghan leaders repeatedly failed to implement reforms demanded by U.S. officials, and Ukrainian commanders reportedly rejected U.S. advice when planning their ill-fated counteroffensive last summer. Kabul and Kyiv were almost totally reliant on U.S. material support, but Washington couldn’t get them to do what it wanted. Similarly, Israeli leaders from David Ben-Gurion to Benjamin Netanyahu have resisted U.S. pressure on numerous occasions—though not always—which suggests that the amount of leverage the United States possesses at any given moment depends on more than the sheer magnitude of U.S. largesse. We should not automatically assume that a phone call from Biden and a threat to cut off U.S. aid would get Israel to do America’s bidding…
Providing client states with economic and military assistance, diplomatic protection, and other benefits gives patrons considerable leverage when they have a near-monopoly on the aid being provided; they care nearly as much as the client about the issue(s) at hand; and there are no domestic obstacles to manipulating the level of aid in order to pressure the client to comply. Leverage decreases if a client can get similar help from someone else, if it cares far more than its patron about the issues in dispute and is therefore willing to pay the price of reduced support, or if the patron cannot reduce its support due to domestic or institutional constraints.
These conditions explain why and how some client states are able and willing to defy the patrons’ preferences. If the patron believes that a weaker ally is intrinsically valuable (e.g., because it is in a vital strategic location, shares similar values, etc.), or if the client’s success is tied to its patron’s reputation or prestige, then the patron will be reluctant to cut a client off even if it is being stubbornly defiant. The Soviet Union had lots of trouble keeping its various Arab client states in line, for example, because they were critical to its influence in the Middle East and the Kremlin didn’t want them to fail (or to realign with the United States). Similarly, the United States could not pressure South Vietnamese or Afghan leaders by threatening to withdraw its support, because it knew these clients would collapse if it did. Presidents Nguyen van Thieu of Vietnam and Hamid Karzai of Afghanistan understood this quite well, of course, which is why Washington found it nearly impossible to control their behavior…
I conclude that Washington does have lots of potential leverage here, and the barriers to using it are lower than they have been in the past. But because Israel’s current leaders remain highly resolved on this issue, even credible threats to reduce U.S. support might not lead them to alter course significantly. Nor is it clear if Biden or his advisors can make the mental adjustments necessary to move from their current failed approach to something more effective. Instead of focusing on whether pressure on Israel would work, the real question to ask is simply whether it is in America’s strategic or moral interest to be actively complicit in a vast and worsening humanitarian tragedy. Even if the United States cannot stop it, it doesn’t have to help make it worse.