How Hard Is It to Dialogue with Iran's Islamist regime?

The idea of dialogue with the Iranian regime breaks down when applied in reality. Here is an anecdote from a source I know to be 100 percent reliable:
 
  Some years ago, a delegation of distinguished Americans went to Iran in order to try to open a dialogue on cultural and environmental matters. They were given a meeting with the environment minister to talk about cooperation. In the meeting, however, he would not let them talk and merely subjected them to a long lecture on all Iran ’s usual complaints and demands.
  Finally, one of the delegation members was able to get in a word and asked if the environment minister would say something about Iran's environmental problems. Here was his full  reply on this issue: "The Number 1 environmental threat to Iran is... the U.S. fleet in the Persian Gulf.