Hello  TedIsAwesome,

Thank you for your contributions to OSM!

The Israeli West Bank barrier cannot be tagged as a boundary because it has an open geometry that cannot be represented as a multipolygon.

https://wiki.openstreetmap.org/w/index.php?title=Relation:boundary&uselang=en says about boundary relations:

They are defined in a similar manner as multipolygons: they must contain at least one outer way, and additional ways can be used to define enclaves or exclaves. 

This changeset was therefore reverted.