An Insular Holding of the United States

Here's FIFA's description of the US Virgin Islands.

"The US Virgin Islands are made up mainly of St. Croix, Saint John and Saint Thomas; a virtual tropical paradise. However, despite the sunshine and ease at play on the USVI, there are dark, ominous clouds gathering on the horizon [FIFA are referring to the Spice Boyz of Grenada].  The national team of the Virgin Islands, an insular holding of the United States, is comprised exclusively of amateur, local-based players, and their reputation in the region's football is similar to that of Montserrat and their British neighbours and namesakes."

An insular holding is an interesting way to describe the relationship.