Regime Change as a Non-Proliferation Strategy

Robert Kagan argues, "Regime change in Tehran is the best nonproliferation policy." Supporting an opposition more open to the West, and seeking to reintegrate into the global economy and internatonial order (a big assumption here) could help reverse, or at least slow Iran's march down the nuclear path. Is regime change the safer than the status quo (doing nothing). Kagan believes regime change is safer than waiting for Iran to build the bomb, or having Israel pre-empt Iranian nuclear facilities which could escalate to a regional conflict. But the "do-nothing" option would in my mind be the more conservative/safer strategy. I should qualify that "do-nothing" also includes passing UN sanctions/resolutions and providing public moral support with more quiet political/economic aid. "Do-nothing" is acutally a safe form of attacking the regime's moral legitimacy. This strategy is the better (or at least more legitimate) strategy in ensuring a safer world than regime change IF Iranians can vote out of power (or topple over) the current government before the regime acquires nuclear weapons.