In the ongoing, years-long group text between my four brothers and sister, there was a brief exchange the Saturday before Memorial Day between me, my son Paul and my next younger brother Perry. I had forwarded Perry a message from Paul, a lieutenant commander in the U.S. Navy serving on a U.S.-flagged commercial tanker between Singapore and the Arabian Sea. In it, Paul related that his ship would be diverted briefly to Diego Garcia, a tiny, Indi…