Congress, led by über-hawks in each chamber, appears to be pushing aggressive measures against Iran that could have unintended consequences ranging from weakening Iran’s embattled opposition to creating a spike in oil prices that would harm global economic recovery and at the same time enriching the Iranian regime.

A new brief from Washington’s Atlantic Council suggests the U.S. should focus its Iran efforts on human rights sanctions and being “creative and flexible” with offers to the Islamic Republic in order to produce a deal that curbs its alleged drive toward nuclear weapons. Pushing further unilateral and extraterritorial sanctions risks alienating allies that have formed the core of international support, said the brief, authored by Council fellow and journalist Barbara Slavin. That international support, meticulously culled by the Obama administration, led to a U.N. Security Council resolution that — unlike many of the U.S. and Europe’s so-called “secondary” unilateral measures — have shown results.

In her brief, Slavin writes:

Piling on yet more stringent and comprehensive penalties — seeking to embargo Iranian oil exports, for example — risks undermining the significant international cooperation the Obama administration have achieved without giving adequate time for the sanctions already imposed to work. “If you push too far, you risk undoing a lot of what they have been able to accomplish,” [Center for Global Development sanctions specialist Kimberly] Elliott said. “If we go for a complete embargo, you’re going to lose everything.”

Congress, though, has spent the past few weeks — coinciding with the big AIPAC conference in Washington — introducing legislation that, according to advocacy groups, comes dangerously close to imposing a de facto oil embargo. In a letter to Capitol Hill released Thursday by, among other groups, the National Iranian American Council, Project On Middle East Democracy, United4Iran, and Americans for Peace Now, the groups said:

We write to express our serious concerns with recently introduced Iran sanctions legislation – H.R.1905 and S.1048.  We take the challenges posed by Iran very seriously, including its nuclear program, its human rights situation, and its role in the Middle East.  As drafted, H.R. 1905 and S.1048 would pose a significant setback to resolving these issues.

H.R.1905 and S.1048  would effectively impose an oil embargo on Iran that could inflict economic costs on the U.S. and humanitarian costs on the Iranian people.  The bills would also weaken the President’s authority to conduct Iran policy and hinder the pursuit of a peaceful resolution to our issues with Iran.  Furthermore, these measures would undermine, not help, Iran’s human rights and democracy movement.

The House version was introduced by Rep. Ileana Ros-Lehtinen (R-Fla), and the Senate version by Sen. Robert Mendez (D-NJ). Both were joined by a bipartisan coterie of Mideast hawks including Sen. Mark Kirk, Congress’s top fundraiser from pro-Israel PACs, who rushed to introduce his part of the bill during AIPAC’s annual Washington conference.

As even one sanctions hawk from a neoconservative think tank has noted, measures that target the Iranian energy sector need to be carefully considered because an all-out embargo could have disastrous effects. The Foundation for the Defense of Democracies‘ Mark Dubowitz recently told the Heritage Foundation:

We’re playing very delicately with a very sensitive oil market and we have to be very careful not to shoot ourselves in the face by going after Iranian crude through an embargo or through the Iran crude oil sanctions act which sends a message to the markets that we’re going to take a million barrels of crude off line next week.

In a recent Wall Street Journal opinion piece, Dubowitz and his FDD colleague Reuel Marc Gerecht (who supports an Israeli attack on Iran and has lousy pro-democracy credentials there) argued that the U.S. could create an “Iranian-Oil-Free Zone” by making it a “hassle” to trade in or use any Iranian petroleum products. One idea was that:

Any company that exports an oil-based product to America—gasoline, plastics, petrochemicals, synthetic fibers—would have to certify that no Iranian oil was involved in its manufacture.

On Thursday at the Atlantic Council event introducing the brief, Slavin said of the measure, “I’m not sure that all these things are practical.” Later, she told ThinkProgress:

What they want is a stealth embargo. And they want it to be slow and quiet so it doesn’t cause shocks to the market, but that’s what they want.

If it starts to look like a total embargo, they will lose support. It starts to look like Iraq.

In the letter to the Hill, the liberal advocacy groups also mentioned Iraq, where seven years of sanctions and an oil embargo caused so dire an economic situation that the infant mortality rate increased three-fold. Of course, that embargo didn’t work. The hawks who pushed Iraq sanctions still went on to successfully push for an invasion of the country in 2003. Perhaps those lessons are why leading Iranian opposition figures like Mehdi Karroubi oppose broad economic sanctions.