United States President Donald Trump announced that on May 12 the US would withdraw from the Iranian nuclear agreement, the Joint Comprehensive Plan of Action, negotiated in 2015 between Iran and the P5+1 countries – US, UK, France, Germany, China, and Russia. The move means the US will reimpose and intensify economic sanctions on Iran within in the next six months on everything from oil, to consumer goods, to banks.

Trump argues that the decision to withdraw from the deal will make the US “much safer,” by forcing Iran to sign onto a more restrictive deal in the near future. However, many world leaders and analysts counter that the move is a serious tactical and strategic error that will obscure current monitoring efforts and prompt Iran to reinstate its program to enrich industrial grade uranium with the objective of building a nuclear weapon. Unfortunately for global security, the later assessment appears to be more probable. The withdrawal will likely increase Iran’s chances of obtaining a nuclear weapon, could drive a wedge between the US and Europe, and may provoke further tension between Iran and its neighbors, notably Saudi Arabia.

Trump is making a risky wager, – that economic sanctions will put enough pressure on Iran to force it to negotiate – which is unlikely to payoff. The US President is overestimating both the speed and effectiveness of sanctions. At best, sanctions have a mixed track record of achieving foreign policy goals. More than a decade of sanctions has done nothing to curb the North Korea nuclear program and sanctions did not convince Saddam Hussein to withdraw his army from Kuwait in 1990. South Africa and Libya are perhaps the two strongest cases for sanction. The countries agreed to give up their nuclear programs in 1989 and 2003 respectively after extended periods of economic sanctions, but it is unclear that sanctions were what caused concessions. In fact, a 2007 study by Hufbauer et al. at the Peterson Institute for International Economics found that unilateral US sanctions, since the 1970s, have only achieved foreign policy objectives 13% of the time.” (Hufbauer et al., 2007) Even the most optimistic assessment would conclude that sanctions take a long time to have an effect and place most of the economic burden on the masses of the target country rather than its ruling elite, which can lead to nefarious consequences.

Not only are sanctions unlikely under usual circumstances, Trump has now embarrassed Iran by reneging on the agreement, rendering Tehran even less likely to negotiate with the US in the future. Even before Trump’s May 8th announcement, the Middle Eastern nation threatened that it would not renegotiate the deal and that it would reactivate its nuclear program if the US reneged on its obligations according to the agreement. Following the announcement, Iranian MPs allegedly burned the American flag and lambasted Trump’s lack of “mental capacity.”

Many political analysts have highlighted that the US withdrawal will facilitate Iran developing a nuclear weapon. Under the terms of deal, Iran has pledged to limit both the quality and quantity of enriched uranium it produces for the next 15 years. It also closed the majority of its nuclear production facilities, reduced the number of its centrifuges, and shipped much of its low-enriched uranium to Russia. But, without the deal, the international community will have no monitoring and verification capacity of Iran’s nuclear progress. Inspectors will lose the ability to carry out snap inspections of nuclear sites and will be denied many of the tools needed to look for secret nuclear sites, such as cameras and sensors in uranium mines, and data and images from on the ground. The US withdrawal will, in fact, relieve pressure on Iran to contain its nuclear ambitions.

Trump may also have caused irreparable damage the US-European alliance, beginning to erode the US’ global leadership position. The three major European players in the deal – Britain, France, and the UK – are attempting to save the deal after the US’ exit, pledging to uphold the accord’s provisions. Iran seems initially receptive, agreeing to negotiate with the other five members to keep the deal in place. President Rouhani has state, “[I]f we can get what we want from a deal without America, then Iran will continue to remain committed to the deal. But if not, Tehran will continue its own path.” Ultimately, the five remaining members of the deal will have to pick camps as Trump has promised to punish any country that violates American sanctions. The US has already pulled out of the Paris Agreement and Trans-Pacific Partnership trade negotiations and it has now disregarded the appeals of its European counterparts to follow through with the agreement. Whether or not the deal continues, the US risks isolating itself further from its European allies.

Lastly, the US withdrawal is likely to increase instability in the Gulf region. International Relations theory identifies information asymmetries about adversaries’ military capabilities as one of three causes of war. (Fearon 1995) Without US oversight and possibly without international monitoring and evaluation of Iran’s nuclear program, Iran’s neighbors, such as Saudi Arabia, will find their positions vis-à-vis Iran increasingly dubious. Uncertainty could cause these states to build up their own military capacities, potentially leading to arms races, or at least, increasing possibilities for misunderstandings between nations. Increased military capabilities could also fuel any of the regions ongoing proxy wars, like that in Yemen or Syria, or lead to an actual confrontation between Iran and its adversaries.