What's at stake for the US in South Africa's ICJ genocide case against Israel?

International Court of Justice expected to determine provisional measures in case alleging Israel is committing genocide against Palestinians

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Israel's allies should look “carefully” at the International Court of Justice's expected provisional measure ruling on Friday in South Africa's genocide case against Israel, experts warn.

South Africa is expecting the ICJ to decide on whether to grant emergency measures to stop the war in Gaza, the first set of decisions in its landmark case accusing Israel of genocide against Palestinians.

But in the US, Israel's most significant and stalwart backer, the response to the case has been one of overwhelming rejection.

President Joe Biden's administration has asserted that it has made no legal assessment about Israel’s conduct in Gaza or whether US weapons may have been misused.

And earlier this week, 210 members of Congress from both sides of the political divide sent a letter to Secretary of State Antony Blinken denouncing the case over claims of South Africa's “deeply hostile stance towards Israel”.

Lisandra Novo, a former judicial fellow at the ICJ, warned that “states that are providing assistance to Israel should look to the wording carefully” in the court's Friday decision.

Though this week's ruling will not deliver a verdict on the genocide case, it will decide on provisional measures which are “essentially emergency measures that the court orders in order to preserve a right that is at risk of irreparable harm”.

The decision this week will be “the equivalent of an injunction order in the US domestic system”, Ms Novo told The National – and that's no small thing.

If the court decides that “at least the possibility on a superficial level [of genocide] exists … it should at least make [Israel's allies] pay close attention to how this assistance is being carried out”, Ms Novo said.

“The parameters of the court orders will be really important to [third-party states] in deciding how you continue forward, the level of assistance and maybe even your involvement with the delivery of assistance and the conditions for receipt,” she added.

For Israel, there are no technical enforcement measures to ensure it halts its Gaza operations following any ICJ decision, but non-compliance “puts them in a very specific category”.

“Right now, one of the most famous states to not comply with provisional measures orders is Russia,” said Ms Novo.

“Do they want to be viewed as members of the international legal community who abide by the norms and the rules set out, that they are rule-of-law-respecting states, or do they go the way of delegitimising the court and pulling out?”

And although South Africa's case against Israel at the ICJ is only binding towards Israel, there could be complicated side effects for Washington.

Cracks have begun to form between US politicians with regard to unilateral political and financial support for Israel as the war in Gaza has unfolded. But growing calls from the Democratic Party for more oversight and even conditions on aid to Israel have failed to materialise.

The Biden administration has twice circumvented Congress to ramp up military sales to Prime Minister Benjamin Netanyahu's government since the war's start and moved to supply billions of dollars in supplemental funding.

If that continues despite an ICJ ruling demanding Israel completely end its military operations in Gaza, “then the United States would be assisting Israel in a direct violation of the court order”, Ms Novo said.

That historic support, some $158 billion worth, especially reinforces Washington's stake as a party to the Genocide Convention.

“The United States is required to 'undertake to prevent and punish' the crime of genocide,” Zaha Hassan, a human rights lawyer and fellow at the Carnegie Endowment for International Peace, argued in a report.

“That commitment becomes meaningless if the United States can simply look away when the party accused of international crimes is an ally or if the outcome of an assessment is inconvenient.

“The United States may want to maintain its certainty that Israel is not committing any grave human rights violations in Gaza by avoiding an assessment, but the ICJ case … may force its hand, even if a decision on the case’s merits takes years.”

Of course, Israel has requested that the case be dismissed. If the court decides in Israel's favour, “nothing happens” after Friday, Ms Novo pointed out.

“It's important to keep other tools in mind if the goal is to end the conflict and to keep political pressure going on other states to come to a solution,” she added.

“To have a very parsed-out decision by a very serious court is a good thing. But of course, that doesn't have the impact that we want right now for the suffering that's going on with the conflict.”