I don't get why the parent was downvoted. Since when does HN get up in arms about grammar nazis? ;) The term "Ex-(French trader)" implies that he could now be, for example, a German trader. I think the proper nomenclature should be "French ex-trader" with the "ex-" prefix being most tightly bound to the thing that the subject was formerly. I may well be wrong about that and I'm fully willing to accept the consequences of the Law of Prescriptive Retaliation. :)

http://languagelog.ldc.upenn.edu/nll/?p=337