You wish the president would embrace these sound, sensible suggestions. Inexplicably, he hasn’t. And nothing in the administration’s public posture suggests that he will change course before Congress votes.

So, what will you do?

Some of your colleagues have floated the idea of a “conditional yes” as an alternative to “approve” and “disapprove.” They, like you, recognize that the agreement has some significant advantages but are deeply troubled by its risks and costs. They want to attach strings to their “yes” vote, in the belief that this will bind the president and improve the deal.

But the legislation enabling Congress to review the Iran deal does not accommodate a “conditional yes.” Votes are to “approve” or “disapprove.” Legislators may negotiate with the White House over every comma and colon in a resolution of conditionality, and they may even secure one or two grudging concessions from the White House. But neither a resolution of Congress calling for these improvements nor ad-hoc understandings between the White House and individual legislators has the force of law or policy. According to the Iran-review legislation, the only thing that matters is a yea or nay on the agreement.

Is there really no “third way”?

The answer is yes, there is. Pursuing it requires understanding what the relevant congressional legislation is really about.

Advocates of the agreement have characterized a congressional vote of disapproval as the opening salvo of the next Middle East war. In reality, a “no” vote may have powerful symbolic value, but it has limited practical impact according to the law. It does not, for example, negate the administration’s vote at the UN Security Council in support of the deal, which sanctified the agreement in international law. Nor does it require the president to enforce U.S.sanctions against Iran with vigor. Its only real meaning is to restrict the president’s authority under the law to suspend nuclear-related sanctions on Iran.

Here’s the catch: By the terms of the nuclear agreement, the president only decides to suspend those sanctions after international inspectors certify that Iran has fulfilled its core requirements. In other words, congressional disapproval has no direct impact on the actions Iran must take under the agreement to shrink its enriched-uranium stockpile, mothball thousands of centrifuges, and deconstruct the core of its Arak plutonium reactor. Most experts believe that process will take six to nine months, or until the spring of 2016.

Why would Iran do all of these things if it can’t count on the United States to suspend sanctions in response? While it’s impossible to predict with certainty how Iranian leaders would react to congressional disapproval of the agreement, I’d argue chances are high that they would follow through on their commitments anyway, because the deal is simply that good for Iran. After Iran fulfills its early obligations, all United Nations and European Union nuclear-related sanctions come to an end. They aren’t just suspended like U.S. sanctions—they are terminated, presenting Iran with the potential for huge financial and political gain.