Trump has wisely avoided war with Iran, but his response to recent attacks on Saudi Arabia have put him on the spot.

The US's initial response, sending more troops to Saudi Arabia, may increase the risk those troops and others face from a longstanding threat, writes intelligence veteran Paul Pillar.

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Although President Trump is wisely resisting starting a new war in the Middle East, the dead-end nature of his failed "maximum pressure" campaign against Iran has put him on the spot to do something, after last week's attacks on Saudi oil facilities, that appears forceful.

He is under pressure to exert more pressure. In response, the administration has been doing two things.

One is to go yet again to the sanctions well. That well is running dry, with the United States having already sanctioned almost every sanctionable thing in the Iranian economy.

About the only practical effect of the administration's newest move on this front, which involves placing a terrorist designation on the Iranian central bank, will be to remove the remaining financial channel for paying for imports of food, medicine, and medical devices—thus contradicting past administration assurances about allowing humanitarian goods to enter Iran.

One possible interpretation of this move is that the administration's assurances have been not only false but especially pernicious in that making the Iranian population suffer in every way possible was always central to the strategy. The civilian suffering would, under this hoped-for scenario, lead either to a popular uprising and regime change or to the Iranian regime lashing out in a way that would give US hawks the war they always wanted.

Pedestrians in eastern Tehran, Iran, August 19, 2019. Associated Press

Another possible interpretation is that the civilian suffering from things like shortages of medicines is not part of the strategy but instead is collateral damage as the administration has become so fixated on the pressure campaign as an end in itself that everything else has become a lower priority.

The other new step the Trump administration has taken in an effort to look tough is to dispatch some more US troops to Saudi Arabia and the United Arab Emirates. This move will augment the deployment this summer of some 500 US military personnel to Saudi Arabia's Prince Sultan Air Base, which was the first such deployment to the kingdom since troop movements associated with the U.S. invasion of Iraq.

The size of the new deployment has been left vague, but reporters were led to understand that the troops involved will number in the hundreds, not thousands.

Secretary of Defense Mark Esper, in announcing the deployment, stated three rationales.

The first is "to send a clear message that the United States supports our partners in the region." This raises questions about whether the message being sent is the most appropriate one to send right now, and about what would be most constructive for the "partners" to do in response.

Does the administration fear that Saudi Arabia will see the need to cool down, rather than further heat up, a military confrontation in the Persian Gulf? That would be very constructive on the Saudis' part, however much it would frustrate the plans of hawks in the US administration. The United States should be giving fewer blank checks and reassurances to the Saudis and instead influencing Riyadh in the direction of conflict resolution. This would include positively responding to the Yemeni Houthis' offer of a compromise settlement of the war in Yemen.

Houthi rebels fighters after a gathering in Sanaa, Yemen, August 1, 2019. Associated Press

The defense secretary's second stated reason for the troop deployment was "to ensure the free flow of resources necessary to support the global economy."

This rationale rings hollow, given that it was the United States, not Iran, that began an attack on the flow of petroleum resources—by using all available political and economic tools of pressure to try to reduce Iranian exports to zero and thereby prevent what would have been substantial production and export of oil from "supporting the global economy."

Esper's third rationale was "to demonstrate our commitment to upholding the international rules-based order that we have long called on Iran to obey."

That, too, rings hollow, given that it was the United States, not Iran, that blatantly violated a multilateral nuclear agreement (the Joint Comprehensive Plan of Action) and has flouted United Nations Security Council Resolution 2231, which was the international community's formal adoption and endorsement of that agreement.

Left unmentioned in Secretary Esper's press conference was how the current crisis, including Iran's part in it, is clearly a direct response to the Trump administration's pressure campaign.

One has to admire the secretary's ability to keep a straight face when uttering a line such as "the United States and other countries have demonstrated great restraint in hopes that Iranian leadership would choose peace" when the administration he serves has attempted to destroy Iran's economy despite what was full Iranian compliance with the JCPOA.

Then-candidate Donald Trump at a "Stop the Iran Deal" rally in Washington, DC, in September 2015. Susan Walsh/AP

It is unclear how much practical military difference the new deployment will make. Probably the main function the US troops will serve is as a trip-wire, in which the early loss of US lives in combat affecting Saudi territory will ensure US involvement in the ensuing war.

That is not a function to be valued. It means reducing US freedom of action and automatically involving the United States in someone else's war. The function also speaks poorly of policymakers who would put their countrymen in a spot where they could die on behalf of the Saudi side of a regional dispute.

Also not mentioned in Secretary Esper's session with the press was another likely way in which those troops could become casualties, which is as targets of terrorist attacks. This hazard is part of a much larger story of how foreign military occupation, or what some locals come to perceive as military occupation, has been a prime motivation for international terrorists. Eastern Saudi Arabia has figured prominently in this story.

Despite the oft-recited mantra about Iran as the "number one state sponsor of terrorism," one has to go back more than two decades to find an operation that met the State Department's definition of terrorism, that drew American blood, and that Iran had a hand in. That was the bombing of the military barracks at Khobar Towers in Saudi Arabia in 1996. It was a direct response to the United States deploying its military on the ground in someone else's neighborhood.

US airmen and soldiers arrive at Prince Sultan Air Base in Saudi Arabia, June 24, 2019. US Air Force/Senior Airman Sean Campbell

The greater danger to the troops in Saudi Arabia may be not from the sort of Shia who did Khobar Towers but from the Sunni extremists who have been the much larger part of anti-US international terrorism in recent decades.

Here again, eastern Saudi Arabia figures prominently. It was the US military buildup there following the Iraqi invasion of Kuwait in 1990 that, more than anything else, radicalized Osama bin Laden and launched him on his terrorist campaign of attacking the "far enemy" of the United States.

These episodes have illustrated counterproductive aspects of US military deployments as far as terrorism is concerned, which usually have outweighed productive aspects whether those deployments were made on behalf of a "war on terror" or for some other declared reason.

The newest deployments are in danger of becoming additional chapters in the same unhappy story.

Paul R. Pillar is non-resident Senior Fellow at the Center for Security Studies of Georgetown University and an Associate Fellow of the Geneva Center for Security Policy. He retired in 2005 from a 28-year career in the US intelligence community.