In reading on this issue this is something that has been in the works for years even before Obama took office. The apparent goal is to blunt Chinese influence in the area. Ironic because the reason we went to Vietnam in the first place was because of concerns over Soviet influence at the time.
But I understand the sentiment of lives being lost over a territory that we are now cultivating into an ally. I guess the same could be said for Japan and other nations who were former enemies. Sometimes there's no sense to be made of it.