Simple answer

We know why the United States, Israel and Britain want to destabilize Iran. The mystery is what is really motivating the 'reformers' within Iran (if you say 'reform', we'll just laugh). The answer may be very simple. Ahmadinejad promised in his first term to root out corruption, and didn't. In Iran, 'corruption' is code for the activities of the Rafsanjani family. Ahmadinejad, known as a straight-shooter, will almost certainly take steps to fulfil his repeated promise this term. The only way Rafsanjani can block this is to stage a coup to attempt to remove Ahmadinejad. Rafsanjani is so desperate he is even ready to risk Ledeen's two-stage plan:

1. coup;
2. in the confusion and violence, Americans install baby Shah as the 'compromise' (perhaps 'compromised' would be more accurate) 'reconciliation' leader.