They attacked targets that symbolize what France is all about. An effective attack on the U.S. requires a strike on the Pentagon and on two massive office buildings where tens of thousands of people go to work every day. An effective attack on France involves entertainment venues. That says everything you need to know about the two countries.
From what we know now about OBL's safe house in Abbottabad and his increasingly exposed relationship with the Pak ISI, it isn't hard to guess what the source of Al Q'aeda's prospective nuclear shipping containers would have been.
And never forget that it was the Chinese "dropped knife" strategy that started all this ... arming all America's worst enemies with nuclear weapons. We haven't yet informed the Chinese what their price will be, of a nuclear attack on the United States, and so this policy will continue to go forward until we do.