From the article:

Gen. Alexus Grynkewich, the head of U.S. European Command, sent written notification to senior Pentagon officials saying that without another Navy destroyer he will be forced to choose defense of the United States “homeland” over that of Israel, said the officials, who like some others spoke on the condition of anonymity to discuss the correspondence.

A U.S. defense official said Grynkewich’s notification appears consistent with past outreach to the Pentagon from the military’s top generals when they see certain risks that require Washington’s consideration. This can occur, the official said, as commanders compete for finite resources and weapons.

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The Navy has been particularly taxed, as the Trump administration has directed a blockade of Iranian ports in response to Tehran’s closure of the Strait of Hormuz. The standoff has stymied the movement of Middle Eastern oil and other commodities through the narrow waterway, upending the global economy.

U.S. naval destroyers in the eastern Mediterranean Sea have been employed as a part of Israel’s defense for many years. The vessels, equipped with powerful radar and armed with an array of missiles, have downed missiles aimed at Israel not only by Iran, but by Houthi militants in Yemen that are equipped by Tehran.

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The Navy has five destroyers that deploy from a U.S. port in Rota, Spain, with a sixth expected to arrive there later this year, Pentagon officials have said. But maintenance issues have piled up due to the Iran war’s tempo, complicating matters for Grynkewich, officials said. The Washington Post withheld specific details about the ships’ availability at the request of military officials, who cited security concerns.

As The Post reported in May, Pentagon assessments conducted earlier in the war showed that U.S. forces have shouldered the brunt of defending Israel from Iranian ballistic missiles. The assessments found that American weapons, including the Terminal High Altitude Area Defense and naval interceptors launched from the eastern Mediterranean, were used far more frequently than Israeli air defense weapons.

Two destroyers, the USS Paul Ignatius and the USS Roosevelt, were in the Mediterranean Sea on Friday, a U.S. official said. Three destroyers were in Rota: the USS Arleigh Burke, the USS Bulkeley and the USS Oscar Austin.