Polls of American public opinion on the agreement to restrict Iran's nuclear program have produced widely varying results. One can find polls to support whatever position one would like to portray as the prevailing public view on this issue. Poll results on this subject are especially sensitive to the wording of the question that is asked. This has meant fertile ground for push-polls, in which questions are worded in a way designed to bring about the result that the sponsor of the poll seeks.

High sensitivity to the wording of the specific question a pollster asks reflects low public knowledge of the subject at hand. It means many members of the public have not focused on the subject enough to form a view that is either strong or well-informed, and that the responses of these people are thus easily swayed by the last words they hear from the poll-taker before answering. It is not surprising that this pattern should be true of opinion on the Iranian nuclear agreement, which involves numerous technical matters well beyond the normal cognizance of most Americans.

Low knowledge of the Iranian nuclear topic has prevailed for some time with the American public, even without getting into technical details of the current agreement. Three years ago the Chicago Council on Global Affairs asked Americans, in a multiple choice question, what was the assessment of the U.S. intelligence services about Iran's nuclear program—an assessment that has been constant over the last several years and repeatedly expressed publicly in statements and testimony. Only 25 percent of respondents picked the correct answer: “Iran is producing some of the technical ability to build nuclear weapons, but has not decided to produce them or not.” A mere four percent erred in the reassuring direction by choosing “Iran is producing nuclear energy strictly for its energy needs.” A plurality, 48 percent, incorrectly chose “Iran has decided to produce nuclear weapons and is actively working to do so, but does not yet have nuclear weapons.” An additional 18 percent chose “Iran now has nuclear weapons.”

It is easy to see how deficient public knowledge on such a subject undermines support for an agreement such as the one before Congress. If one believes that Iran is intent on finding a way to acquire nuclear weapons—or even worse, as nearly a fifth of respondents believed, that it already has such weapons—that puts the agreement in a very different, and unfavorable, light than if one understands that the agreement is a bargain that trades sanctions relief for Iran committing itself to remain a non-nuclear-weapons state and subjecting itself to restrictions that ensure it remains one. And in general, greater knowledge about the agreement and the issues it entails is associated with support for the agreement, and lesser knowledge is associated with opposition to it.

This pattern has been reflected in polling results that have shown greater public support for the agreement when some explanation of what the agreement is about is offered than when no such explanation is given. The pattern was particularly clear in a recent CNN poll that split the sampled population in two and asked each half a different version of the question about support for the new agreement. One-half was asked a bare-bones version of the question: "As you may know, the U.S. Congress must approve the agreement the United States and five other countries reached with Iran that is aimed at preventing Iran from developing nuclear weapons before it can take effect. Do you think Congress should approve or reject the deal with Iran?" Among these respondents, 41 percent said accept and 56 percent said reject. The question presented to the other half provided just a bit more explanation: "As you may know, the U.S. and other countries have imposed strict economic sanctions against Iran while that country has nuclear facilities which could eventually allow it to produce its own nuclear weapons. Do you favor or oppose an agreement that would ease some of those economic sanctions and in exchange require Iran to accept major restrictions on its nuclear program but not end it completely and submit to greater international inspection of its nuclear facilities?" Here the result was 50 percent saying favor and 46 saying oppose.

To CNN's credit, the second question does not seem to be slanted either for or against the agreement. If one were to get very picky and try to find any such bias, one would be at least as able to see a slant going against the agreement as in favor of it. After all, the question points out that Iran's program includes facilities that "could eventually allow it to produce its own nuclear weapons" and that the agreement would "not end [the program] completely". And yet, even the very small amount of explanation yielded significantly more support for the agreement than the other question did, to the extent that the plurality was reversed. (To its discredit, CNN then in its own news coverage focused on the half of the poll result that showed disapproval and ignored the other half.)

Mustering support for the agreement thus has consisted in large part of educating the public about the deal itself and about the issues at stake regarding its fate in Congress. Mustering opposition to the agreement has consisted of whatever is the opposite of public education. That has included obscuring the basic nature of the issue at stake, especially by criticizing terms of the agreement without noting how the alternative of no agreement would be distinctly worse on the very points on which the agreement is criticized. It has included throwing every possible argument against the agreement up on a wall and seeing what sticks, without regard to whether the entire barrage has any coherence or internal consistency. It has included encouraging the public not to learn about the agreement so much as merely to feel disgust at doing any business with a detested Iranian regime. And it has included seizing on any detail or leak that, if creatively misinterpreted, can be portrayed as a major flaw.

That last tactic has been much in evidence regarding international inspections in Iran. It was in evidence most recently with the accusation that Iran would be allowed "to do its own inspections" at a non-nuclear military facility that has been the subject of old accusations about work said to have been done there years ago. The accusation is simply untrue, and there is no reason to believe, even taking the leaked supposed fragment of a draft agreement at face value, that inspection arrangements at that facility or anywhere else in Iran will depart from well-established standards of scrutiny by the International Atomic Energy Agency.

The tactic also has repeatedly surfaced with what became the "24-day" issue on inspections. The provision in the agreement that was seized upon in that case has nothing whatever to do with inspection of Iran's declared nuclear facilities, which will be subject to continuous monitoring. Even with undeclared, non-nuclear facilities the required advance notice is 24 hours, not 24 days. The provision that has been seized upon, far from being a loophole, was added as a further safeguard so that in the worst possible case, if Iran balked at a demanded inspection, a procedure would be in place to ensure that Iran would be outvoted and the inspection would take place (or in the very worst possible case, Iran would be found to be in violation with everything that implies regarding sanctions). Issues regarding inspection of undeclared facilities also have been treated in an anti-educational way by opponents of the agreement in that attention has been diverted from what really matters in any worrying about potential Iranian violations. What matters is not some single piece of work or equipment that could evade both inspectors' environmental swipes and the scrutiny of national intelligence services but rather a Manhattan Project-scale infrastructure—which would be too big to evade detection, especially with the enhanced international monitoring of all aspects of the nuclear fuel cycle.

The chief consequence of the exploitation (and encouragement) of public ignorance and misunderstanding by opponents of the nuclear agreement is that the matter has become a much closer call in Congress than it ever should have been, especially given that the agreement is not at all risky for the United States because the United States is not giving anything up except for some of the punishment it doles out, and that the agreement is clearly superior to the alternative of no agreement and no special restrictions on the Iranian program. A subsidiary consequence is the corruption and degradation of public debate, as illustrated by the aforementioned inspection issues.

That in turn has led to a lot of debate about the debate, and not just about the substantive issues. President Obama has taken criticism for the candid way in which he has spoken, especially in his speech earlier this month at American University, about the nature of the opposition to the agreement. The criticism is valid only insofar as the president could have given more of a nod to those who are genuinely confused or conflicted, are sincerely trying to arrive at a well-founded opinion about the accord, and amid the confusing arguments have honest concerns and reservations. They are the victims of the exploitation of ignorance, not the exploiters. With regard to the exploiters—those driving the opposition to the agreement—the president was speaking the truth.

The message that members of Congress ought to take away from the polls is that as far as public opinion is concerned, members have ample space to make a principled decision about the nuclear agreement. They do not have to fight against some well-entrenched public view. They will not suffer a backlash of public opinion—genuine public opinion—if they do their own part in educating the public and explaining the reasons for their position.

A gold standard for such education and explanation was set by Representative Jerrold Nadler, the New York Democrat who last week accompanied his announcement of support for the agreement with a remarkably thorough 5,200-word statement giving the reasons for his decision. The statement is one of the most insightful analyses of the relevant issues to come out of Congress or anywhere else, and it is very useful reading for any citizen looking for guidance and education on the subject. Not every member of Congress can be expected to be as thorough and diligent as Nadler has been, but he has shown what can be done along this line.

Members who come out differently are not necessarily intellectually lazy or incapable of understanding the relevant issues—and most of them aren't—nor are they misreading the public opinion polls. But they are being subjected to pressures that involve the role of money in politics, the Citizens United decision, and related matters that go beyond the direct influence being exerted on the Iran nuclear issue. This gets into reasons why even on some issues on which the American public does have a firm and reasonably well-informed prevailing view, such as Social Security, there still are significant political forces pushing in a different direction. It is for those general reasons, as well as the more specific sources of opposition to the Iranian nuclear agreement, that some members of Congress are exhibiting profiles in lack of courage. They are missing a good opportunity to show real leadership of the American public.