Ok, thank you everyone, this has been helpful. I do not have any concrete plans for moving back to the US, but I would like to travel back and forth freely with my wife, and allow her the rights of being married to a US citizen. Right now we are waiting for her approval to get a tourist visa, but even then she can be denied entry at the whim of any US immigration officer at the airport, so it is quite scary. I know Colombians with US spouses who have been denied entry. But as far as I can tell nothing can be done.