1. First we'd have to very meticulously define "open border policy", as this could be defined and designed in many different ways.
(We could easily come up with 20 different definitions of "open border policy"... and if we do, then it would be virtually impossible to tell if it's addressed in the bible, or what the biblical view would be... as different definitions could actually contradict each other.)
2. After we've picked ONE DEFINITION, one VERY PRECISE DEFINITION, we could then discuss the OP's question.
3. Most likely, it isn't something that's really addressed in the Bible at all... but that may depend on what kind of definition we choose.