Welcome to FR!
"French looking" began as term of derision, directed at Presidential candidate, John F'n Kerry. While Kerry, who I hear served in Vietnam, has some Irish features and an Irish name, he recently discovered that he was half Jewish.
Then he and the ketchup heiress started defending the French and bragging how they both spoke French. Some one in Washington, perhaps the White House, commented that he looked 'French'. This of course was going on while the French government was working against us while we were seeking UN approval for the war in Iraq.
Now, 'French looking' is part of the FR vernacular, like calling someone a 'Clymer'.
Just don't ask me to explain 'Breck Girl'.