Precisely. Look, if a Polish American had the necessary drive and accompanying skillset, they'd be in the picture too.
Nope, sorry to burst your bubble!
But for example as Timken was nominated by the Bushies to become ambassador to Berlin the german TV run a very interesting doku how ambassadors come to be appointed by Washington in the first place...
An interesting picture emerged...the more someone spends money to support the voting campaign of the winner/now US president the more he can now demand back.
These ambassadors have rarely any diplomatic background at all or are studied diplomats, foreign specialists or whatever, rarely speak any lingua beside english, often just very rich entrepreneurs (if you are lucky they bring with them some business contacts and connections)
who are bored and want to try something new.
Why not a prestigious but harmless post?
Most US-Ambassadors are of that kind...exceptions confirm the rule!
PS: If a Pole would had spend millions for Obama and now would show interest he would had had a good chance to get the ambassador post in Warsaw.(Nothing to do with skillset at all...)