Nearest international waters to Yemen is deep into the Indian ocean.
I doubt that Yemeni missiles would be a threat so far away.
Here's the news media story about the aftermath of the multiple attacks the Houthis made in US and other ships, some of which were in a trade capacity.
Former U.S. Navy HSV-2 Swift wrecked in Yemen missile attack
The HSV-2 Swift, formerly an original proof-of-concept ship for the U.S. Navy’s Joint High Speed Vessel program, was gutted by explosion and fire when Houthi rebels attacked the ship off Yemen Oct.
www.workboat.com
US enters Yemen war, bombing Houthis who launched missiles at navy ship
Pentagon says radar sites were attacked after the destroyer USS Mason came under attack and notes ‘we will respond to any further threat’
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