This should not be such an arduous task. Years of incompetent economic mismanagement and growing repression have created an already unbridgeable gap between the regime and its people. Sanctions should aim to broaden that gap even further. Economic pressure must increase the already widespread discontent and help turn economic dissatisfaction into political mobilisation. Sanctions, therefore, should be designed and enhanced to serve a different purpose — not so much a change of behaviour as a change of regime.

Critics will no doubt say that tougher economic measures could harm ordinary Iranians and drive them into the arms of the regime. They forget how deadly the regime's embrace is. Iranians, by contrast, know it all too well. Despite four years of international sanctions, they rarely blame the West for their economic distress. As for the opposition, their tepid condemnation of sanctions was coupled by an indictment of the regime's policies as the main cause of Iranian isolation. If accompanied by a robust public diplomacy effort designed to keep the Iranian public informed, sanctions can further alienate them from their rulers.

With this in mind, the West must ratchet up the pressure even further while speaking directly to the Iranian people about what its goals are — that ultimately, its long-term strategic interest of preventing a nuclear-armed Iran is best served by the overthrow of the Islamic Republic. The guiding principle of Western policy should not be more pointless negotiations with Iran's ruthless rulers, but the restoration of the fundamental freedoms of ordinary Iranians.