Story highlights Experts say it sends a message to China

The move could be a boon to U.S. companies

(CNN) President Barack Obama's announcement Monday that he was lifting the ban on the sale of weapons to Vietnam sent one message to the former U.S. wartime foe and another to the region.

By ending the ban, the U.S. is signaling its desire to leave behind decades of tense post-war relations with Vietnam and start a new phase of closer economic and military ties -- one facet of the "rebalance" toward Asia that's central to the president's foreign policy legacy.

At the same time, the U.S. is showing the region -- and particularly China -- that it is committed to maintaining international rules in Asia and to backing up smaller countries in area where tensions have been rising as an increasingly assertive Beijing tries to establish maritime claims in the South China Sea.

"The decision to lift the ban was not based on China or any other considerations," Obama said in Hanoi Monday. "It was based on our desire to complete what has been a lengthy process of moving towards normalization with Vietnam."

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Obama added that part of U.S. cooperation with Vietnam is aimed at improving their maritime security posture "for a whole host of reasons," including strong defense ties. "But I want to emphasize that my decision to lift the ban really was more reflective of the changing nature of the relationship," he said.

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