Iran is on course to develop nuclear weapons. Few foreign policy challenges pose a greater threat to the security of the United States and our allies. To permanently and verifiably prevent Iranian nuclear weapons, America must be united and resolute. History and common sense indicate this is more likely if congressional approval is required of any final agreement negotiated by the president.

For half a century, Congress has reviewed, amended and voted on treaties that have achieved lasting results with nuclear disarmament. In fact, many of these agreements have enjoyed broad bipartisan support on Capitol Hill. Since 1955, the United States has entered into roughly 25 Section 123 Agreements with various countries, including Canada, Japan, China and more than 27 European nations. SALT I, SALT II and START are other examples in which both Republican and Democratic presidents have worked with congressional leaders of both parties to achieve consensus on international nuclear agreements. Often the affirmation was overwhelming.

In the Iranian context, congressional authorization would carry the added benefit of illustrating America’s commitment to long-term Iranian nuclear deterrence beyond the end of the Obama administration in January 2017. Iran is more likely to make meaning concessions when our government speaks with one voice and our commitments and deterrents extend beyond 20 months.

In addition, congressional approval of an Iranian nuclear accord that included specific and automatic consequences for listed violations would carry added weight. Congressional authorization for the use of force in case of egregious cheating by Tehran is particularly important. Iran may doubt our resolve following Syria’s use of chemical weapons in defiance of America’s warnings. There must be no doubt about the price they will pay for non-compliance with any nuclear weapons limitations.

The administration will be tempted to act unilaterally and not seek congressional concurrence. Previous presidents were similarly tempted, and engagement with the legislative branch can take time, try one’s patience and necessitate refinements to any accord. But ultimately this is the course most likely to result in a lasting, effective, resolution. To do otherwise would leave large parts of Congress and the American people hostile to the agreement, not a strong foundation for American security or lasting arms control.

Members of the Senate have rightfully maintained that a meaningful congressional response to Iran’s intransigence would restore common sense sanctions and take into consideration flexibility in support of ongoing negotiations. The American Security Initiative was founded with these objectives in mind and the desire to build bipartisan support for these goals. It is our hope the Senate leadership will bring the Lindsey Graham-Bob Corker measure to the floor in March for a vote.

The Iranians are pursuing a nuclear weapon, not peaceful energy development, and the United States must remain vigilant in eliminating their capacity for uranium enrichment. Stopping Iran’s nuclear ambitions constitutes one of the most critical foreign policy threats our nation faces. Congressional oversight and approval not only has precedence, it remains indispensable in order for America to send an unequivocal message to our allies, and underscore with Tehran, that under no circumstances will we allow Iran to acquire nuclear weapons.

Evan Bayh, a Democrat, is a former senator from Indiana. Saxby Chambliss, a Republican, is a former senator from Georgia. Norm Coleman, a Republican, is a former senator from Minnesota. All three serve as board members of the American Security Initiative.