I don't know the reason of doing all the stuff was motivated to serve the best interest of the people of the United States or just to serve his own interest of leaving his name in history ?
Obama seemed to explode into getting the fire started without proper planning ahead and follow up plan. Signing 11.6 billion contract between Vietnam and Boeing is one thing ( BTW, why do we need the President of the United States to sign a commercial contract ? ) open full board arms trade with Vietnam is another matter.
Not to go into other obvious issues, the Chinese was not pleased with this action and could trigger , fuse the future actions.
What's your take on this ?