The whole piece is worth reading, but I was struck by this unearthed quote:

....Thérèse Delpech, a leading nonproliferation expert at France's Atomic Energy Commission, warned last October at a Brookings Institution lecture, "We [the Europeans] have negotiated during five years with the Iranians . . . and we came to the conclusion that they are not interested at all in negotiating, but . . . [only] in buying time for their military program." In those five years, she also noted, Tehran never implied that if only the Americans were at the table the clerical regime would be amenable to compromise.