By Phil Stewart and Humeyra Pamuk

WASHINGTON (Reuters) – Hours after Iranian missiles rained down on Israel on Oct. 1, President Joe Biden's administration sent an urgent message to Israel: Take a breath.

Washington argued that Israel, which received U.S. military support, had time to decide how to respond to the Iranian strike. The attack, assessed as potentially lethal, could have killed thousands if not countered effectively by Israel.

Officials feared a sharp Israeli response could escalate tensions, pushing the Middle East towards all-out war, especially with upcoming U.S. elections. Current and former U.S. officials recount how the U.S. sought to guide Israeli actions during the three weeks before Israel’s military response.

Israel eventually conducted airstrikes targeting Iranian military assets, destroying key air defenses and missile facilities while avoiding sensitive nuclear sites, aligning with Biden's main demands. Jonathan Panikoff, a former U.S. intelligence officer, noted that without U.S. pressure, Israeli decisions might have differed significantly.

Israeli Prime Minister Benjamin Netanyahu refuted claims that the targets were chosen due to American pressure, claiming they were determined by Israel's national interests.

The Biden administration's first move was to acknowledge that Iran would face consequences for its Oct. 1 attack. U.S. Defense Secretary Lloyd Austin held multiple discussions with his Israeli counterpart, pushing for a proportional response. Ensuring Israel would respond, Secretary of State Antony Blinken communicated with European and Arab allies about Washington's efforts for a calibrated Israeli action.

Despite the Oct. 1 strike resulting in minimal casualties—one Palestinian death—some Iranian missiles evaded interception, suggesting Israeli defenses faced challenges. Jeffrey Lewis, a Middlebury Institute expert, speculated Israel may have sought to conserve its defense resources while assessing repair costs.

As U.S. calls with Israel began, potential Iranian targets included nuclear and oil sites, although the U.S. aimed to provide alternatives. The U.S. proposed oil sanctions targeting Iran's “Ghost Fleet” as a means for Israel to address Iran’s oil revenues without military action.

Moreover, the Biden administration enhanced Israeli air defenses ahead of the anticipated strike by deploying the Terminal High Altitude Area Defense (THAAD) system and military personnel. U.S. conversations with Netanyahu prior to this deployment ensured an understanding of Israeli plans.

Iran cautioned against targeting its supporters, while Gulf states maintained neutrality. Following Israel's intent to disrupt Iran's oil sector, the U.S. imposed expanded sanctions against Iranian petroleum and petrochemicals.

The U.S. also struck Iran-aligned Houthis in Yemen, demonstrating military capabilities. Washington assured Israel of support if Iran pursued nuclear weapon development, emphasizing the current inappropriateness of escalation.

Blinken conveyed to Arab ministers that Israel was expected to limit its strikes to military targets, hoping this message reached Tehran. As the situation stabilized post-attack, neither side signaled further confrontation, though U.S. officials remained alert to any Iranian retaliatory actions.

Biden's restrained approach towards Israel faces criticism from Republicans who argue it restricts Israel's abilities to counter Iran. However, experts suggest the ongoing strikes could inadvertently increase Israel's risk tolerance, with possible implications depending on the outcome of the upcoming U.S. presidential election.