Fox News reported that a squadron of F-15E fighter jets had arrived in the United Arab Emirates as part of the deployment that had been ordered the previous month, in response to intelligence concerning the potential for Iranian attacks. The USS Abraham Lincoln has been operating in the waters outside the Persian Gulf as part of that same military action, and a B-52 bomber task force has flown training missions in coordination with the aircraft carrier group. Additionally, 900 support troops were deployed to the region, while 600 others had their deployments extended.

Separately, it was announced late on Monday that this previous deployment would be roughly doubled with another 1,000 soldiers. Fox noted that neither deployment was intended to serve a combat function but would instead provide support “for the fighter squadrons currently deployed, the Patriot anti-aircraft missile batteries and engineers.”
This is in keeping with President Donald Trump’s repeated insistence that he has no desire for war with Iran, but is concerned with providing sufficient deterrence against Iranian provocations, as well as against the possibility of accelerated nuclear activity.

On Monday, the Islamic Republic reiterated its warnings about the future of the 2015 nuclear deal, formally known as the Joint Comprehensive Plan of Action. Although the US withdrew from that agreement last year, its European signatories have sought to preserve it and have urged the Iranians to continue complying with its provisions. Up to this point, the International Atomic Energy Agency has reported that they have been doing so, but Iran has repeatedly insisted that the European Union provide financial incentives to defray the effects of US sanctions that were re-imposed in August and November.

Iran’s nuclear facilities have already reportedly ceased to limit their output of nuclear material, putting them on pace to exceed limits that were set by the JCPOA. Officials have also indicated that if they are not satisfied with European measures by the middle of next week, those facilities will immediately begin enriching uranium to a higher fissile purity, and thus closer to the threshold for weapons grade.

German Chancellor Angela Merkel responded to Tehran’s ultimatum on Tuesday by saying that if the Iranian regime follows through with its plans to blatantly violate the nuclear deal, “there will of course be consequences.” But it was not immediately clear what, if any, particular consequences the governments of Germany, France, and the United Kingdom were willing to commit to. It therefore remains to be seen whether the European powers might sign onto the Trump administration’s policy of “maximum pressure,” consisting both of economic sanctions and the still-increasing military deterrents.

Naturally, the administration seized upon Tehran’s threats to encourage broader cooperation with European allies. National Security spokesman Garrett Marquis was quoted as saying, “President Trump has made it clear that he will never allow Iran to develop nuclear weapons. The regime’s nuclear blackmail must be met with increased international pressure.” He also used the opportunity to repeat the president’s criticism of the JCPOA’s limited scope and duration, and to reaffirm the administration’s commitment to securing a more comprehensive deal that addresses such issues as Iran’s ballistic missile development and its regional imperialism.

But it is this latter issue, rather than the longstanding threats over the future of the JCPOA, which appears to be the primary motivator for the White House’s latest military deployments. Last week, two commercial tankers in the Gulf of Oman were damaged by explosions, and the Trump administration moved quickly to attribute those incidents to Iranian limpet mines. As Secretary of State Mike Pompeo pointed out, the use of these weapons has long been established as a tactic of the Islamic Republic, and not regional proxy group has either the resources or the know-how to emulate such attacks.

In the immediate aftermath of Thursday’s attacks, the US military released drone surveillance footage that purported to show members of the Islamic Revolutionary Guard Corps removing an unexploded mine from the hull of one of the targeted vessels, the Japanese-owned Kokuka Courageous. On Monday evening, the White House followed up on this with higher-resolution images of the apparent mine and the IRGC recovery, as further evidence of the notion that Iranian forces had carried out the attacks and then taken measures to cover their tracks.

Despite those measures, the US reportedly recovered additional evidence from the damaged ships which implicated Iran. This includes mine fragments and handprints from the person or persons who removed the object from the Kokuka Courageous. Additionally, US officials made reference to “other intelligence” that suggests Iran has been “conducting low-level attacks against shipping and other targets,” according to the Los Angeles Times. This presumably includes intelligence attributing four tanker explosions last month to the Islamic Republic. Taking place off the coast of the United Arab Emirates, these too have been blamed on Iranian limpet mines.

To whatever extent the relevant intelligence has already been shared among the US and its allies, it has apparently been sufficient to convince some of them of Iran’s guilt. The United Kingdom was nearly as quick as the US in accepting this conclusion, and the Guardian newspaper reported that this assessment was still standing on Tuesday, although “there is not understood to be any immediate plans for the UK to step up its military commitment.”

Then again, this is not something that the US government has demanded of its European allies, at least not in response to the tanker attacks specifically. In a possible reflection of his aversion to military entanglements in the Middle East, Trump sought to downplay those attacks on Monday, characterizing them as “very minor” and emphasizing that the US is not nearly as dependent on oil trade passing through the Persian Gulf as it once was. This ostensibly reduces the likelihood of American forces acting to unilaterally safeguard that trade against Iranian mines as they did during the “tanker wars” in the 1980s. And this may in turn assuage some concerns about the potential for the US and Iran to unwittingly stumble into open conflict.

When asked directly about the prospect of military confrontation, Trump indicated that he would be willing to use this as a tool to prevent Iran from obtaining nuclear weapons, but would be less likely to address other issues in this way. And despite continuing to describe the Islamic Republic as a “nation of terror” in the wake of the tanker attacks, the president suggested that extreme measures would not be necessary in order to compel a change of behavior, which he believes to already be emerging as a result of the pressure his administration is exerting on the clerical regime. Referring to anti-American slogans that have defined that regime since the 1979 revolution, Trump said, “I’m not hearing that too much anymore, and I don’t expect to.”

This is particularly optimistic in light of the fact that the White House strategy of maximum pressure is still developing, and still awaiting potential assistance from the European Union and the international community more generally. The State Department explained that Secretary Pompeo was meeting with leading military commanders in the Middle East on Tuesday to “discuss regional security concerns and ongoing operations,” including plans for the newly deployed support troops. Meanwhile, General Paul J. Selva, vice chairman of the Joint Chiefs of Staff, said that the US was reaching out to regional partners as part of an effort to build necessary “international consensus” for any actions against the Islamic Republic.

In explaining the latest military deployments on Tuesday, Secretary Pompeo once again emphasized that the White House is working to avert war through deterrence. And in the interest of urging regional and Western partners to contribute to that deterrence, he also highlighted the long history of Iranian aggression and malign behavior, of which last week’s tanker explosions are just the latest examples. “Forty years of Iranian activity… has led us to this point,” he said. “We shouldn’t focus on just these two attacks.”