WASHINGTON — The Trump administration on Wednesday published an executive order declaring it is now formal US policy to guarantee Qatar’s security against foreign attack, following unprecedented Israeli airstrikes last month that targeted Hamas officials in Doha, the capital of the small Gulf state.

“The state of Qatar has hosted United States forces, enabled critical security operations, and stood as a steadfast ally in pursuit of peace, stability and prosperity, both in the Middle East and abroad, including as a mediator that has assisted the United States’ attempts to resolve significant regional and global conflicts,” according to the text published by the White House and dated Sept. 29.

“In light of the continuing threats to the State of Qatar posed by foreign aggression, it is the policy of the United States to guarantee the security and territorial integrity of the State of Qatar against external attack.”

Why it matters: The new policy goes further than existing US defense arrangements with other Arab states in the Gulf, which for decades have looked to Washington to ensure their security but without receiving explicit guarantees of protection.