Many people understand credibility to mean something like “sticking to one’s word” or “following through on one’s commitments.” By this standard, President Trump’s Tuesday decision to withdraw the United States from the Iran Deal (formally, the Joint Comprehensive Plan of Action, or JCPOA) would bolster Trump’s credibility. After all, during his campaign he claimed it was his “number one priority to dismantle the disastrous deal with Iran.”

A year and a half into his term, he has now followed through on the promise. Trump’s boosters believe that his “tough” stance will show the North Koreans, who are currently poised to enter talks with the U.S., that the president will only accept the best of deals.

Just one problem: Credibility has nothing to do with following through on one’s word. With regards to threats, for instance, empirical studies overwhelmingly show that no one looks back at their rivals’ previous statements and tabulates their follow-through record. What matters are the stakes a country has in a particular outcome and the power dynamics between the countries in question.

With regards to agreements, strategic credibility boils down to whether or not potential allies have a sense that if they throw in their lot with you, it will likely work out well for them. This is all people really care about when they are considering an alliance: a positive outcome. And by this standard, reneging on the Iran Deal is disastrous for American credibility.

The JCPOA, taken at face value, was a landmark agreement, showing that even some of the world’s most difficult and pressing problems could be peaceably resolved through good-faith multilateral cooperation. By a number of expert accounts, the deal worked. In recent weeks several senior U.S. military officers and Israeli security officials have forcefully urged the president to stick to the deal—in the interest of U.S. and Israeli national security, and for the sake of U.S. credibility in the world. The IAEA certified Iran as fully compliant with the terms of the agreement. The other parties to the agreement verified this intelligence and urged the United States to rely on IAEA reports and stick to international agreements. To no avail.

Leading up to the deal, many countries took hits to their own economies in order to “bring Iran to the negotiating table” through sanctions, while their negotiators spent years hammering out the details of one of the most comprehensive multilateral arms-control agreements ever produced. The deal has subsequently proved to be an economic boon not just for Iran, but also the EU and China, thanks to Iran’s oil and gas resources.

Then the U.S. president withdrew, casting the entire deal into jeopardy. Not just Iran, or future rogue states, but also key European allies must now reevaluate the way they deal with the U.S. And this makes the outcomes Trump is aiming for by withdrawing from the deal far less likely to be realized.

Ostensibly, Trump is hoping to negotiate a “better deal”: Iran is expected to not only accept even more restrictions on its nuclear activities, but also to abandon key defense projects and virtually abstain from geopolitics.

On its face, it would be insane for the Islamic Republic to agree to these terms—no matter the economic costs—given that they are surrounded by two failed states (Iraq, Afghanistan), another country on the brink (Pakistan) and a rival across the Persian Gulf who is committed to their regime’s destruction (Saudi Arabia). Then there’s Israel a few states over, possessing a formidable military and led by a man who has long cheered the prospect of regime change in the Islamic Republic.  

Even in a world where the U.S. president seemed credible, and offered complete normalization with Iran in exchange for these concessions, it would be a tough deal to take. But Trump is not offering complete normalization, and the U.S. has lost strategic credibility on this issue with Iran. At this point it seems implausible that it could ever be restored.

This is the second time in recent history that a state has entered into a nuclear agreement with the U.S. only to be betrayed by the subsequent administration.

In 2005, Muammar Gaddafi struck an agreement with George W. Bush not only to end his nuclear program, but to transfer nuclear materials out of the country, and to cooperate on counter-terrorism initiatives. He fulfilled his end of the deal, but was nonetheless deposed during the controversial and problematic humanitarian intervention of 2012.

Nonetheless, Iran took a chance on Barack Obama. They entered into the most sweeping arms control deal of its kind ever negotiated—making unpopular and at times painful concessions throughout. President Rouhani staked his domestic legitimacy on being able to change how the world interacted with Iran. The Islamic Republic has complied fully with the agreement. All for naught, it would seem: After a change in the White House, the U.S. has not only violated the terms of the agreement by reinstating the sanctions, but is once again talking about regime change in Iran, according to Rudy Giuliani’s comments to an Iranian opposition group last week.

Consequently, there will be no “better” deal. What would be the point of Iran signing a new agreement with a party that has refused to abide by the first one? Especially given the knowledge that—even on the off chance that Trump managed to honor an agreement for the duration of his tenure and does not pursue regime-change in Iran—any eventual successor could nonetheless scrap the deal on a whim, and issue new demands down the line.

But the stakes are hardly limited to Iran: the U.S. is currently trying to negotiate nuclear disarmament of North Korea, a new trade deal with China (one of the JCPOA signatories Trump has potentially alienated), and a retooling of NAFTA. At some point, the U.S. will return to brokering a deal between Israel and Palestine, and negotiating a lasting peace in Afghanistan, Iraq and Syria. It is unlikely that North Korea, China, Russia, Mexico, Canada, Palestine, Afghanistan, Iraq or Syria find Trump to be more “credible” as a result of shredding the Iran Deal. More likely than not, these negotiations will grow much more fraught and complicated as a result of Trump’s ill-conceived strategy with Iran.