There is progress in the long-term struggle to achieve a nuclear agreement with Iran. Reliable reports indicate the United States and Iran have moved toward compromise.

Current focus is on a possible accord that would strictly limit Iran’s nuclear development for a decade, to be followed by reduction of the limitations, plus easing harsh economic sanctions.

Negotiations have been challenging but continue. The international P5+1 group negotiating with Iran consists of Britain, China, France, Russia and the U.S. — the five permanent members of the United Nations Security Council — plus Germany, an extremely important trading partner of Iran.

Secretary of State John Kerry took a brief break for testimony before Congress on Feb. 24. He effectively emphasized both progress in negotiation, and the U.S. commitment that Iran will not be permitted to develop nuclear weapons. He deserves special commendation for leading the extremely tough, complex negotiations with Tehran, while juggling a wide range of other policy responsibilities.

Meanwhile, U.S. senators have re-emerged to try to derail the fragile interim nuclear agreement with Iran. In the last Congress, Senators Mark Kirk (R-Ill.), Robert Menendez (D-N.J.) and Charles Schumer (D-N.Y.) joined in bipartisan mischief to introduce legislation titled the Nuclear Weapon Free Iran Act.

The proposed legislation would permit members of Congress to scrutinize and second-guess decisions and evaluations of the executive branch and the International Atomic Energy Agency (IAEA). Strict time limits are imposed on reaching a final nuclear agreement with Iran. Also included is yet one more dramatic declaration of the commitment of the U.S. to defend Israel.

This proposal was not brought to a vote, but since then Senate control has passed from Democrats to Republicans. The bill has been reintroduced.

A further current complication is the invitation from Republicans House Speaker John Boehner to Israel Prime Minister Benjamin Netanyahu to address Congress. The Netanyahu government adamantly opposes the negotiations with Iran. He is to address Congress on March 3, over the strenuous objections of the Obama administration.

Given the overheated rhetoric emanating from Iran, Israel and U.S., several facts should be highlighted. First, there is no evidence Iran actually is constructing a nuclear weapon, and the government in Tehran has cooperated with IAEA inspectors.

Second, Iran’s leaders have shown restraint in use of force. In 1988, near the end of the long Iran-Iraq war, Saddam Hussein’s brutal regime launched massive poison gas attacks against Iran, killing and maiming thousands of people. Iraq was at the time a U.S. ally. Tehran did not respond in kind.

That same year, U.S. naval forces mistakenly destroyed an Iranian civilian airliner, killing nearly 300 people. Tehran did not retaliate, and a financial settlement was reached.

Third, economic sanctions have had a significant negative impact on Iran’s economy. In 2012, the currency dropped 80 percent. Without a nuclear agreement, sanctions on Iran could eventually destroy the economy.

Fourth, U.S. foreign policy is the responsibility of the president. The most significant modern congressional challenge to this executive authority was the Bricker Amendment, a shorthand reference to a series of proposals in the 1950s spearheaded by Sen. John Bricker (R-Ohio), the 1944 Republican vice presidential nominee.

President Dwight D. Eisenhower worked tirelessly against this constitutional threat, yet won in the Senate by only one vote. Eisenhower described the battle as one of the most exhausting – and important – of all his dealings with Congress.
Arthur I. Cyr is Clausen Distinguished Professor at Carthage College and author of “After the Cold War” (Macmillan and NYU Press). He can be reached at acyr@carthage.edu.