Surprisingly, the Iranians welcomed the "humanitarian gesture."

CNN:

U.S. sailors from a carrier strike group whose recent presence in the Persian Gulf drew the ire of Iranian military officials have rescued 13 of the Middle Eastern country's sailors from a hijacked fishing boat, a military spokesman said Friday.

The destroyer USS Kidd came to the aid of the ship Thursday in the North Arabian sea, near the crucial Strait of Hormuz, according to the Navy.

The rescue prompted the captain of the freed ship to offer his "sincere gratitude," according to Josh Schminky, a Navy Criminal Investigative Service agent aboard the Kidd.

"He was afraid that without our help, they could have been there for months," Schminky said.

[...]

The Navy team provided food, water and medical care to both the suspected pirates and the crew of the Al Molai after securing the ship and ensuring everyone was safe, Schminky said.

The crew had "been though a lot," he said.

"We went out of our way to treat the fishing crew with kindness and respect," he said.

Secretary of State Leon Panetta called the USS Stennis later Friday to congratulate the strike group commander, Rear Adm. Craig Faller, and his team on a "well executed effort," the Pentagon said.

Meanwhile, the Revolutionary Guards will conduct massive naval exercises in the Gulf according to the Fars News Agency, The gesture won't change the tension that is building between Iran and the US, nor head off a probable confrontation this spring.