Open Border With Mexico; What Does That Mean?

It would be smart long-term to have a 50 to 70 year plan where we can have an open border with Mexico. But that is not doable right now or in the best interest of our country you see? An open border right now would be total suicide for the United State's Economy, but we need to work towards that future goal and put in place reasonable safe guards, which indeed allow for trade, tourism and travel.

Recently in an online think thank one member mentioned that no one really understands what an open border policy really means and stated;