Obama administration officials hoping to end the nuclear standoff with Iran not only face a nation legendary for hard-line negotiating, they also must deal with members of Congress who may be just as unyielding.
In talks with Iran set to resume in Geneva in mid-October, the White House must weigh two competing challenges: coaxing Tehran to stop uranium enrichment and other nuclear work, and winning support from a Congress that is skeptical of easing sanctions against Iran.
In an era when Congress is divided on almost everything, the desire to bash Iran is nearly universal on Capitol Hill, unitingtea party conservatives such as Sen. Ted Cruz (R-Texas) and liberals like House Minority Leader Rep. Nancy Pelosi (D-San Francisco).
Since only Congress can permanently lift the bruising sanctions it has imposed on Iran, lawmakers can torpedo any deal if they believe the White House is giving too much to Iran's pragmatic new president, Hassan Rouhani, or his hard-line boss, supreme leader Ayatollah Ali Khamenei.
"We have a tremendous amount of leverage," said Rep. Ed Royce (R-Fullerton), chairman of the House Foreign Affairs Committee and co-author of the toughest Iran sanctions legislation ever adopted by the House.
If the Senate passes the bill, which the House approved in July by a vote of 400 to 20, the U.S. would seek to cut Iran's oil exports — which account for 80% of Iranian government revenue — to near zero by punishing purchasers. The bill would also take a long step toward clamping a total trade embargo on Iran.
Royce made it clear that he doesn't trust the conciliatory overtures Rouhani made during his recent visit to the United Nations, or during his 15-minute phone call with President Obama on Sept. 27.
"Their best hope is to draw things out through negotiations, while they continue their nuclear work," Royce said.
Obama and Rouhani are both eager to avoid war, and have incentive to compromise. Diplomats say a possible deal might allow Iran to enrich uranium to low levels for peaceful purposes under strict oversight by theInternational Atomic Energy Agency, or import nuclear fuel from Russia or other countries.
To some extent, the aggressive approach on Capitol Hill sets up a good-cop, bad-cop dynamic between the White House and Congress that can provide potential leverage for U.S. officials if the talks in Geneva lead to further negotiations, experts said.
U.S. negotiators can tell the Iranians that if they don't give ground on their nuclear program, "those crazy people on the Hill might do anything," said Mark Dubowitz, a sanctions specialist at the Foundation for Defense of Democracies, a pro-sanctions advocacy group.
The long reach of U.S. sanctions law means the White House "really has to treat Congress as a full partner on this issue," said Dubowitz, who has been an advisor to lawmakers on the issue.