In the wake of the multifaceted failure of the Trump administration’s policy of “maximum pressure,” the advent of the Biden administration will make possible a more effective U.S. approach toward Iran. Return to compliance with the multilateral nuclear agreement known as the Joint Comprehensive Plan of Action will slash Iran’s stockpile of enriched uranium to one-twelfth of what it has amassed in response to Trump’s policies. Iran will no longer have reason to attack other oil producers’ facilities when the United States is no longer trying to destroy Iran’s own trade. And U.S. discrediting of Iranian moderates and strengthening of Iranian hardliners will end.

Some American voices, however, including some sympathetic to President-elect Biden, have been suggesting that as long as the outgoing administration has piled up all those sanctions against Iran, the incoming administration ought to try to make use of them as leverage to somehow squeeze out of Tehran an agreement more favorable to the United States than the JCPOA. Such suggestions are related to comments — being made in response to Biden’s appointment of many former officials in Barack Obama’s administration — that “the world has changed” in the last four years and that Biden should not try to recreate what Obama created and Trump destroyed.

Such observations have a bit of validity. Useful elements sometimes can be found in policies that overall are abject failures. The fact that Trump did something ought not to be an automatic cause for rejecting that something. To do so would only be a new version of Trump’s own destructive habit of doing the opposite of whatever his predecessor did, simply because his predecessor did it.

The suggestions regarding sanctions and leverage on Iran, however, are contrary both to the way international influence works in general and to the specific circumstances involving Iran.

The ingredients of leverage

Leverage — in international relations as in other situations — requires making treatment of the target of leverage conditional. Treatment must depend on what the target country does. Desirable behavior elicits rewards or at least an absence of punishment; undesirable behavior is punished with treatment that hurts.

Punishing the target country regardless of its behavior does not create leverage; it destroys it. That’s what the Trump administration has done by reneging on its obligations under the JCPOA, and United Nations Security Council Resolution 2231, even though Iran was fully complying with its own obligations. Iran continued to comply for a year after the Trump administration’s reneging, but the Trump people just added still more punishment and escalated to all-out economic warfare.

When Iranian leaders see their country being punished no matter what it does, the incentive for them to comply with agreements and behave the way we would like to see them behave vanishes. They start looking instead for ways to exert pressure back, which is exactly what Iran has been doing over the past year and a half in response to the Trump policies. Iranian leaders perceive — probably correctly — that the true objective of Mike Pompeo and others shaping the Trump administration’s policies on Iran has been regime change. Regime change is the ultimate killer of incentives for good behavior. Why comply with the wishes of someone who is determined to get rid of you anyway?

Both sides of the leverage equation are equally important. The prospect of hurtful treatment in response to undesirable behavior must be credible, but so must the prospect of favorable treatment in response to compliant behavior. Right now the credibility deficit of the United States is on the latter side of the equation. If the Biden administration were to continue Trump’s economic warfare — which was in violation of international agreements and Security Council resolutions, and entirely unwarranted in light of Iranian compliance — to try to pressure Iran into a different agreement, Iranian leaders would see this as just more of the same.

The U.S. credibility needed for Tehran to take a chance on a new agreement with Washington would still be lacking. The Iranian moderates who were made to look like fools by Trump’s reneging on the JCPOA would look even more foolish if they took a similar chance again, even if the faces in Washington had changed. Iranian hardliners would become even more entrenched.

Upholding agreements

Iranian leaders have indicated they are willing to talk and negotiate, at a suitable time and under suitable circumstances, about issues beyond those covered by the JCPOA and Resolution 2231. But they have been adamant in rejecting any renegotiation of the JCPOA itself. That position is unsurprising and understandable. The Iranians don’t want to be tricked into buying the same horse twice.

It is hard for Americans to accept that anything an Iranian leader says is reasonable and understandable. But imagine if the roles were reversed — if Iran wanted to renegotiate the JCPOA to give itself economic benefits or give its nuclear program more leeway. The response of everyone on the U.S. side, not to mention the other JCPOA participants, would, of course, be immediate rejection of the idea and emphatic expression of the principle that a deal’s a deal.

The JCPOA was the product of long and difficult negotiations. To paraphrase a sports cliché, the members of each team left it all on the negotiating table. Those negotiations demonstrated two limits of what was possible. One was that there would be no agreement on the nuclear issue if each side loaded up the agenda with its other grievances (and remember that Iran has plenty of grievances against the United States). The other was that there would be no nuclear agreement until and unless the United States abandoned its earlier insistence that Iran enrich no uranium.

The current suggestion about the Biden administration trying to exploit the Trump-imposed sanctions is merely the latest version of a notion heard in this country throughout the four-decade history of the Islamic Republic of Iran — that by exerting pressure just a little longer, the Iranian rulers will cry uncle over whatever issue we want them to cry uncle about. That notion has not worked for the last four decades. It clearly has not worked over the last four years. There is no reason to expect it to work over the next four.

There will be room for wider discussions and negotiations with Iran in the future, provided the United States recognizes two realities. One is that to get more it will have to give more — especially giving Iran greater assurance it will get the sort of economic relief it expected under the JCPOA but never fully got even while Obama was in office. The other is that agreements on some issues, such as restrictions on missiles, will be feasible only if addressed on a regional basis rather than singling out Iran.

But to get to that land of broader negotiations will first require the United States to live up to agreements it already has made, rather than trying to wring advantage out of a patently failed policy.