At every critical moment along the diplomatic path to a resolution of Iran’s nuclear program, vocal members of Congress have threatened to impose new sanctions that could torpedo the process. Last Friday, when Iran and the P5+1 powers, the U.S., Russia, China, Britain, France and Germany, announced they would continue talks through a new hard deadline on November 24, was no exception. While this extension should be hailed as a victory for the United States, this belligerent, vocal minority continues to threaten the resolution of this decades-long, vexing foreign policy problem.

Led by the House Committee on Foreign Affairs Chairman Ed Royce, R-Calif., and ranking member Eliot L. Engel, D-N.Y., nearly 350 House members sent a letter to President Obama last week that was full of demands on Iran. The letter asserts that Iran must permanently and veritably terminate not only its nuclear program but also its ballistic missile program, support for international terrorism, and other unconventional weapons programs. Additionally, these members expect restrictions on Iranian banks designed to stymie proliferation, terrorism, money laundering and other activities abetting to global terrorism.

Similarly, Senate Foreign Relations Committee Chairman Robert Menendez, D-N.J., and Lindsey Graham, R-S.C., a ranking member, are also circulating a letter for signatures. Among other things, the letter demands that Iran “dismantle its illicit nuclear infrastructure, including the Fordow enrichment facility and the Arak heavy water reactor, such that Iran does not retain a uranium or plutonium path to a weapon.”

These letters amount to Congress making overly specific (and sometimes unnecessary) demands in a negotiation to which it was not invited. The goals are certainly laudable, but such rigorous requirements put the cart woefully before the horse by invoking issues far outside the parameters of discussion about Iran’s nuclear program.

Never one to be one-upped in political brinksmanship, Sen. Ted Cruz, R-Texas, said on Tuesday that he would introduce legislation that renews strong sanctions with an enforcement mechanism and calls for the complete dismantlement of Iran’s nuclear program. He declared the Joint Plan of Action a “historic mistake” that entailed “conceding everything at the outset and hoping for good faith.” Given that the floodgates of international business into Iran have not opened and most of Iran’s citizens continue to feel the crushing economic impact, Cruz’s statement sounds as outlandish as it is reactionary. His jab at “good faith” also ignores that the IAEA has verified Iranian compliance with every requirement thus far.

The real question is what these members want. If they, like the administration and the leaders of the world, want to stop Iran from developing a nuclear weapon, they are acting directly against that interest. It is abundantly clear that these initiatives will only impede and possibly derail a final, long-term deal to curb Iran’s development a nuclear program.

The alternative to a negotiated settlement is as clear as it is bleak: an unchecked Iran with no incentives to stop pursuing its nuclear weapons capability and a raison d’être for the most robust defenses possible. Following that is the uncertainty: Would Israel follow up on its word to act unilaterally against Iran? Would the U.S. be then compelled to join in some military capacity?

What would the American people have to say to their elected representatives then, and what would their answer be when asked if they fully pursued all diplomatic options? The prognosis is not favorable. Recent polling showing robust American support for a diplomatic solution (62 percent of Republicans and 65 percent of Democrats — a remarkably bipartisan consensus) make it hard to see how all this blustering reflects the will of the American people.

As with any negotiation, Congress should assess our bottom line and consider the alternatives to a negotiated settlement. Yes, the U.S. and our allies would be safer if Iran agreed to completely dismantle its nuclear program, admitted past weaponization aspirations, and stopped funding terrorist networks across the region. Unfortunately, that is unrealistic.

Without a long-term negotiated settlement, Iran has very little incentive to further curb its nuclear program, and no incentive to let inspectors in. The threat of any continued and unchecked pursuit of a nuclear weapon, given its ongoing support for non-state terrorist actors will unequivocally make the world less safe. Continuing the negotiations towards a permanent solution is absolutely essential.

Sanctions enacted with cooperation between Democrats, Republicans, legislators, and executives did their part to force Iran to the table last November. Now, mainstream politicians and the American people have made it clear that they prefer a diplomatic solution and have very little appetite for yet another military engagement overseas. Hardliners in Congress must stop demanding a pie in the sky long-term deal that very few experts, pundits, or analysts see as remotely possible. Instead, they need to act responsibly to preserve a critical U.S. national security interest.

John M. King serves as vice chair on the Board of CleanTX and the Austin Young Chamber of Commerce. He is also a partner of the Truman National Security Project.