Diplomatic gaffe threatens red (white and blue) faces all round during King and Queen's visit to Virginia's Arlington National Cemetery... but can you spot what's wrong?

At Arlington National Cemetery, one of the United States' most significant sites of military remembrance, in Virginia on Thursday, King Charles paid a touching tribute.

Diplomatic gaffe threatens red (white and blue) faces all round during King and Queen's visit to Virginia's Arlington National Cemetery... but can you spot what's wrong?
At Arlington National Cemetery, one of the United States' most significant sites of military remembrance, in Virginia on Thursday, King Charles paid a touching tribute.