The text of the letter also provides further evidence of the general lack of trust that much of the US Congress has regarding Obama’s handling of those negotiations. “In reviewing such an agreement, Congress must be convinced that its terms foreclose any pathway to a bomb,” the letter said, implying that the president might otherwise leave certain pathways open.

“Only then,” it continued, “will Congress be able to consider permanent sanctions relief.” Certain economic sanctions have been imposed on Iran by the American legislature and would have to be permanently removed by the same. But in opposing Congress’s efforts to have a larger role in the deal making process, the Obama administration has played up its ability to remove other sanctions unilaterally, and also to waive some of the legislative sanctions on a temporary basis.

Radio Free Europe / Radio Liberty confirmed the president’s general narrative on this topic in an “Explainer” article on Monday. It brief history of Iran sanctions points out that most of them were imposed by executive order, including those that were introduced in 2002 in response to the revelation of secret Iranian nuclear sites by the National Council of Resistance of Iran.

The congressional sanctions primarily dealt with broader issues of Iran’s weapons development and support for global terrorism. It is also worth noting that the 2010 supplement to the Iran Sanctions Act was signed into law by President Barack Obama, possibly suggesting that his administration has not been as committed to a soft line on Iran as some of its opponents assert.

This supplement, known by the acronym CISADA, already requires the sort of verification demanded by Congress before its sanctions can be lifted. This verification must demonstrate to Congress not only that Iran has ceased to pursue nuclear weapons, but also that it is not pursuing other weapons of mass destruction, further developing its ballistic missile arsenals, or continuing to support terrorist organizations.

While the nuclear negotiations seem to have partly undermined the president’s commitment to such measures, there is also evidence that he is still wary about Iran’s activities beyond its nuclear program. An article published Monday by the Washington Times indicates that the US led coalition has apparently held back air support in the midst of the siege of ISIL-held Tikrit, specifically out of fear of empowering Iran-led Shiite militias.

Of course, the danger of such empowerment of Iran and its proxies is something that has been cited by Obama’s critics as a general consequence of his policies of dealing softly with Iran and encouraging cooperation with it against Sunni militants in Iraq.

And as the Washington Times also points out, this cooperation has worked against American interests in the sense that it has allowed Iran to come to be viewed by Baghdad as a more reliable partner than the United States. This perception is arguably reinforced by the supposed “static” situation that the forces at Tikrit now find themselves in.

Breaking the stalemate would not undermine the sense of Iraq’s closeness to Iran, which is growing steadily. Neither would American air support at Tikrit be likely to be publicly acknowledged by Iran or by its proxies and allies in Iraq. “We say we do not need the Americans,” said Shiite militia leader Hadi al-Ameri, echoing the sentiment expressed by Iran, which has contradicted analysts’ reports about the effectiveness of the coalition bombings, arguing that that coalition could be replaced by one comprised entirely of Iran and its allies.

Any such coalition, and any empowerment of Iran at all, could pose a significant challenge to US interests in the Middle East region. While the Obama administration has effectively acknowledged that it is using the Shiite side of local conflicts against ISIL, the decision to hold back at Tikrit may indicate that the US is also hedging against the threat of Iranian ascendancy.

This perception is further supported by the news of an ongoing training operation in the Middle East known as Eagle Resolve. The exercises by 3,000 diverse US military personnel are being hosted by Kuwait, a first for the Arab state and member of the Gulf Cooperation Council, which is headed by Iran’s main regional rival, Saudi Arabia.

The proxy conflicts between Iran and Saudi Arabia have escalated in recent weeks despite previous speculation that the two powers might be courting rapprochement. The deterioration of their relations has especially been sped along by Iran’s support for the Houthi rebels in Yemen, which recently forced the Saudi and US-supported president of Yemen to flee to the south of the country, effectively dividing it in two, bringing forth new sectarian conflicts, and causing the situation to inch ever closer to civil war.

The worsening situation in Yemen has just compelled the United States to withdraw the last of its personnel from the country, according to Reuters. The boosted American military presence on the north side of the Persian Gulf may somewhat counterbalance this. And in any event, although the US has denied that Eagle Resolve has anything to do with the Iran nuclear talks or Iran’s current regional activities, the timing of the operation is conspicuous and the Washington Free Beacon indicates that this makes it easy to view the operation as sending a warning to Iran and a message of support to the US’s existing Middle Eastern allies.

But there is little reason to expect such messages to be effective if the Obama administration’s policies move in the direction of general rapprochement and cooperation between the US and Iran, as his critics fear they will. John Jenkins of the International Institute for Strategic Studies expressed this fear on Monday when he was quoted by Reuters in an article on Iran’s expansion of its “empire” in advance of a deadline for a framework nuclear agreement at the end of this month.

He acknowledges that the US military presence in the region is as strong as it has ever been – something that is evidenced by the Eagle Resolve maneuvers – but he adds that Americans allies in the Gulf region are increasingly doubtful about the US’s willingness to actually act in opposition to Iranian ascendancy.

“Already we see Iranian officials saying that they control four Arab capitals, and we have seen Houthi delegations travel to Tehran and Baghdad. This plays into the Gulf Arab narrative that they are being sold down the river,” says Jenkins.

Quoted in the same report, a United Arab Emirates commentator named Sultan al-Qassemi argues, “The Iranian deal is a game-changer for the region and I think it is going to encourage Iran to pursue an even more assertive foreign policy.”

This expansion would build upon a situation already deemed unacceptable by many of Iran’s critics and opponents, including no less highly-placed a personality that Iraqi Vice President Iyad Allawi. The National Council of Resistance of Iran points out that Allawi recently said of Tehran, “Doing what they are doing and sending officers to fight and to lead, and declaring that Baghdad is becoming the capital of the Persian empire, is unacceptable.”

As Iran News Update reported previously, Iranian President Hassan Rouhani’s close advisor Ali Younessi declared early this month that Iran and Iraq must necessarily choose between either fighting each other or being unified as one. Depending on which policies it continues to follow with respect to Iran, the United States may be in a position to either prove this statement false or facilitate Iran’s more aggressive pursuit of such unity with its neighbor to the west.