Some of the strongest challenges to Iran's Islamic Republic come from the very people who helped build it, which complicates any simple story about who leads the opposition.

• Figures like Montazeri, Karubi and Mousavi were insiders and allies of Khomeini before turning against the system they created.
• Their protest movement pushed the government close to collapse, showing the threat comes from inside as much as outside.
• Backing the regime early on does not disqualify someone from leading opposition to it now.
• The same argument cuts the other way: leftist intellectuals working inside the old Shah's court is read as a sign of breadth, not weakness.
• Trotsky is the parallel — a founder of the Communist Party who became one of its sharpest critics.

Outlook: Iran's opposition will likely keep drawing leaders from former insiders, keeping the fight over who has the right to lead alive.