04/27/2010 05:12 am ET Updated May 25, 2011

With Sanctions Against Iran, Congress Should Defer to the President

Congress is trying to assume control of US policy toward Iran by legislating severe trade sanctions. Nothing would be more damaging to US policy.

For the first time in three decades a President has forged an intelligent, transparent and multifaceted strategy for dealing with Iran. Unlike past policies, this calibrated confrontation using sticks mixed with dangling carrots has widespread international support. Ironically, it may be Congress, not China, which derails effective US sanctions.

The Senate and House bills now in conference committee would require the President to embargo all refined petroleum products imported into Iran. But these restrictions actually penalize any US or foreign company that sells or transports gasoline or home heating oil to Iran. Because these would require a substantial investment of US intelligence, interdiction and military resources to implement they are unrealistic. Moreover, they will cost the US the international support so critical to any sanctions success.

Recent sanctions episodes show that such excessively punitive sanctions usually fail. Truly smart sanctions do not simply damage and enrage the target. They also provide a roadmap that re-engages it with the international community on the issues which have created the crisis. Obama's second diplomatic track to discuss an exchange of nuclear fuel with Iran complements well Treasury's new round of sanctions. Congress can never wield this kind of versatility and timeliness.

Congressional legislation is particularly ill-suited to the nimble mix of measures needed to prompt nuclear restraint in Iran. Past successes in the Ukraine, South Africa and Libya illustrate that only an astute use of narrowly targeted sanctions on those most responsible for nuclear development combined with new security guarantees and a versatile array of economic incentives lead countries to denuclearize. The challenge in these situations was not increasing the severity of sanctions. If Congress wants to advance US goals, it might work on the larger set of incentives needed to seal a future nuclear deal.

Many Senate and House members believe that imposing devastating sanctions against the Iranian government and the Islamic Revolutionary Guard Corps will increase the Iranian opposition movement's success. But sanctions have never toppled a rights-violating government. Sanctions improve the human rights behavior of leaders only when the imposing nation severely curtails its own extensive bilateral aid, trade, investment, and banking with the target. This is the sanctions paradox: they are much more effective against economically interdependent friends than already ostracized enemies.

If Congressional sanctions were passed, these measures will drive a jack-hammer through the Iranian economy when a scalpel is needed to change the behavior of Iranian elites. Of all times when the US does not need to impose new hardships on the Iranian people it certainly is not now when the new opposition movement is still forming its own agenda against the regime.

The South African case reminds us that outsiders should not impose crippling embargoes unless and until the leadership of the opposition movement calls for them. Then these sanctioners should act firmly and quickly. This is beginning to occur among Iranians, as figures like Shirin Ebadi call for political sanctions, not crippling economic ones, in response to Tehran's human rights abuses. The President, not Congress, is best positioned to adapt and readjust targeted sanctions accordingly. And the Administration is becoming increasingly focused on the human rights dimensions of its carrots and sticks.

This situation parallels what the Clinton Administration faced in 1995 in the Conoco Deal. Then some US companies were exploring a thaw in Iranian business outreach. Congress, driven by some of the same lobbying groups that push current legislation, reacted by preparing strong sanctions measures. The prospect of Congressional sanctions setting US policy pushed Clinton to pre-empt the legislation by blocking the Conoco Oil company's pending $1 billion deal with Tehran. In hindsight, such business dealings that increased positive cooperation between Tehran and Washington, as monitored by the Administration, may have put US-Iranian relations on a better course than we now face.

If Congress wants to enhance US strategic objectives like ending Iran's weapons program and its human rights abuses, then it must provide the President with sanctions flexibility. In particular, Congress must make a significant procedural change in the legislation being discussed in conference committee. They should revise the Senate version requiring that the President impose petroleum sanctions in favor of authorizing the President to enact such restrictions at his discretion. This will maximize the President's sanctions leverage.

By George A. Lopez

George A. Lopez holds the Hesburgh Chair in Peace Studies at the Kroc Institute, University of Notre Dame. In 2009-10 he is a Jennings Randolph Senior Fellow at the United States Institute of Peace where he is writing a book on the future of economic sanctions. The views expressed here are his alone and not those of USIP.