President Trump has an Iran problem. He has inherited a nuclear deal that he opposes but that he cannot change. The financial and economic sanctions that forced Iran to negotiate are largely gone and ending the agreement would remove controls over Iran's nuclear activities. Trump's current approach is rhetoric, sticking to the nuclear deal, minor sanctions, and a policy review. Instead, he needs a strategy to fill President Barack Obama's policy gaps on nuclear weapons research, missiles, and human rights.

Trump's first step must be to demand Iran reveal all its weaponization research. The world must know exactly how far the Islamic Republic progressed and which countries helped it. Without this knowledge, and given the regime's record of cheating, Iran will seek a nuclear weapon when the deal's restrictions start expiring after 2027. Without full disclosure, the Iran agreement delays, but does not deny, the Islamic Republic's nuclear weapons ambitions.

Obama folded on weaponization. Then Secretary of State John Kerry covered up this failure by claiming that "We know what they did. We have no doubt. We have absolute knowledge with respect to the certain military activities they were engaged in."

Actually, we don't.

Getting Iran to "fess up" may prove impossible. However, Trump can make Iran pay for intransigence. He can instruct U.S. diplomats at the International Atomic Energy Agency, the UN's nuclear watchdog, to stop all attempts to mainstream Iran's nuclear program and so lift residual sanctions. This will happen if the IAEA reaches "the Broader Conclusion that all nuclear material in Iran remains in peaceful activities." Russia, Iran's ally, has already called for the IAEA to reach this conclusion.

Second, Trump should insist on limits on all Iranian missiles. Kerry negotiated UN Security Council Resolution 2231 (2015) which asks Iran not to work on or launch "ballistic missiles designed to be capable of delivering nuclear weapons." This polite request lasts at most for eight years after the Iran deal.

The problem is that Iran's missile program goes beyond nuclear delivery systems. Its missile arsenal exists to intimidate the rest of the Middle East, which is why Iran tested three ballistic missiles in March alone. Trump should demand that Iran restrict its missiles to a maximum 300 kilometer (186 miles) range and a 500 kilogram (1,100 lbs) payload—limits consistent with the internationally-agreed Missile Technology Control Regime. Trump can apply sanctions and encourage further sales of anti-missile systems to U.S. allies to blunt the effect of Iran's missile arsenal.

Finally, Trump should make Iran pay for its human rights violations. The Islamic Republic tortures, imprisons, and murders. It denies freedom of conscience to the Bahá'í religious minority and hangs hundreds of Arabs, Baluchis, and Kurds with little pretense at due process. The regime commits war crimes in Syria and exports terrorism globally. Contrary to Obama, Iranian threats to the existence and independence of other countries are not rhetoric. Destroying another state is the ultimate human rights violation.

Obama used the regime's dismal record to pressure Tehran into entering nuclear negotiations. That's why Obama stopped U.S. human rights programs for Iran from being too effective. That's also why Obama barely used sanctions legislation against human rights abusers—the E.U. sanctioned more Iranians for human rights abuses than the U.S.

Trump can sanction those who order repression. The main culprit is Ayatollah Ali Khamenei, the so-called Supreme Leader. Then there is former President Mahmoud Ahmadinejad, responsible for the crackdown after he stole the 2009 presidential election. Finally, there is Hassan Rouhani, the fake moderate who was recently re-elected. Rouhani has overseen a massive increase in executions.

To be credible on human rights, however, Trump must allow Iranians to travel to the U.S. following proper vetting. The president's executive order of March 6 demands that the Islamic Republic provide information on Iranians to the U.S. government. It makes no sense for the U.S. to trust the Iranian government's judgement on its citizens, especially on dissidents. Trump's immigration ban hands the unpopular Tehran dictatorship an undeserved propaganda victory.

Trump has called the nuclear agreement with Iran "the worst deal ever negotiated." That is a soundbite. If Trump is to protect the Middle East from Iran, he needs a strategy.

Andrew Apostolou was the Director for Iran at Freedom House.

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