As the Washington Examiner characterizes the situation, those lawmakers are now “jumping at the last chance” to prevent the planned lifting of economic sanctions against Iran. But the Washington Post notes that the backlash against the ballistic missile tests has come both from Obama’s traditional enemies and from his allies, including some of those who support the nuclear deal.

 Representing the latter group, Democratic Senator Chris Coons expressed support for the Obama administration’s broader policies but said of the October and November ballistic missile tests, which violate UN resolutions, “We have to have a menu of responses that we and our allies have agreed on and that we will take. Or the Iranians will pocket it and keep moving.” This reflects the fear that an inadequate response to the weapons violations will embolden Iran to make violations in other areas, on the expectation that there will be no consequences.

 Samantha Power, the US ambassador to the UN, has indicated that the missile tests would be discussed by the UN Security Council. But it is not yet clear whether any serious action will be taken by the international body, and some analysts are certainly doubtful. Thus, according to the Post many lawmakers, including Democrats, feel that the US must be prepared to act unilaterally if necessary.

 An editorial that appeared in Legal Insurrection last week explained that the only way to secure Iranian compliance is to “vocally and powerfully respond to any violations.” This assessment was applied both to the recently violated UN resolutions and to the nuclear agreement, or Joint Comprehensive Plan of Action. By the Obama administration’s own admission, the JCPOA is a non-binding agreement and can only be enforced insofar as the international community is empowered to expose Iranian violations and respond to them with the re-imposition of economic sanctions.

 But many of Obama’s critics doubt both the willingness and the ability of Western powers to actually follow through on this point. And these concerns have been further focused on the International Atomic Energy Agency’s report on past military dimensions, which will be the basis for the UN vote on Tuesday.

 Breitbart reported on Friday that Republican Representative Ed Royce, the chairman of the House Foreign Affairs Committee, said that a resolution to close the file on past military dimensions will send a clear signal that there will be no consequences for Iranian duplicity and misbehavior. While the report ostensibly provides a complete assessment of Iran’s prior activities, it also acknowledges that the Islamic Republic had continued work on some elements of a nuclear weapons program at least until 2009, longer than previously believed. Furthermore, it points out that Iran’s cooperation with the IAEA probe was limited and was characterized by periodic efforts to stonewall and mislead nuclear inspectors.

 Breitbart also quoted Olli Heinonen, a former deputy director general of the IAEA, as saying that the unanswered questions left by the final report could have negative consequences for the ability of the world community to monitor Iran’s future activities.

 On Monday, a Wall Street Journal editorial referred to both the missile tests and the instances of non-cooperation with the IAEA as reasons why the apparent US strategy of non-confrontation may not be workable. The article pointed out that the Obama administration and its allies have been trying to “defuse tension” by focusing on the future instead of the past. But Iran has been focusing on the future in exactly the opposite way, keeping its nuclear options open with missile tests, secrecy, and a strictly limited approach to its implementation of agreed-upon changes to its program. 

 The editorial therefore concludes, as other critics have done in the run-up to Tuesday’s vote, that IAEA investigations of that program should continue. If the UN heeds this advice, it may well complicate or even halt the implementation of the JCPOA, since Iranian Supreme Leader Ali Khamenei has insisted that the issue of past military dimensions must be closed before Iran undertakes some of the essential changes that it must complete before the deal goes into full effect.

 Still, recent criticisms suggest that for many supporters of the deal, this is a worthwhile risk in order to prevent the Islamic Republic from taking advantage of Western good will. At the same time, opponents of the deal would likely be pleased if an assertive response to the IAEA report and the ballistic missile tests resulted in Iran personally derailing the agreement. There is little doubt that many of those opponents still view that deal in the same way as it was characterized by Israeli Prime Minister Benjamin Netanyahu: as paving the way to an Iranian nuclear weapon, rather than preventing it.