NavList:

>>"almost-landlocked Germany"  Better not tell the Germans. etc. etc.<<

I stand corrected in several respects.  Thank you!

You could be right about surveying only places of commercial importance. 

Perhaps the Americans survey the USVI so frequently because several cruise ships a day dock there...and the BVIs get surveyed infrequently because only a few cruise ships a month arrive...and THEY anchor outside the port of Road Town.  Though with out-of-date soundings, anchoring well outside the port is probably the best way for a large vessel to stay safe on the British side...and they might even decide that a visit to the US side of the VIs was preferable/simpler/safer.

"Commercial importance" and "updated charts" may stand in a bit of a chicken/egg relationship.  Without updated charts, you might be less likely to GROW in your commercial importance.

The Americans have scaled back on their world-wide charting, as have the British.  35 years ago, I got charts to sail in Japan from what was then known as the US Defense Mapping Agency.  They probably still KEEP charts of the everywhere for military use, but in terms of what they sell to the public, you need to go to various national cartography agencies (such as the Canadian Hydrographic Office) or to NV, who publishes charts that the national agency may have allowed to lapse...even when those charts relate to one of their own overseas territories.

Bob