Iran’s nuclear talks with the P5+1 (five permanent members of the UN Security Council and Germany) in Geneva resulted in an “interim” agreement last Saturday. It obliges Iran to verify the peaceful nature of its nuclear program, and to dilute its stockpile of highly enriched uranium under international supervision, in return for limited sanctions relief. Iran has agreed to halt all enrichment above 5 percent and to dismantle the technical equipment for higher-grade enrichment.

The howls of rage (“Munich!”) from various predictable quarters notwithstanding, this agreement and the comprehensive one to be negotiated early in the new year is fair and balanced. It will make it virtually impossible for Iran to pursue a nuclear weapons program. The critics accuse the soft-spoken President Hassan Rouhani, who is committed to ending Iran’s international isolation and the economic sanctions, of being a wolf in sheep’s clothing. “Iran is an enemy,” former Senator Joe Lieberman told CNN on Monday, and that statement sums up the position of the deal’s opponents. They complain that current Iranian capabilities remain in place, and that it has effectively gained the recognition of its right to enrich uranium for nuclear power generation. Most Americans disagree: supporters of the deal outnumber its opponents by two-to-one.

In the end Iran will accept the supervision of its nuclear activities in return for the complete lifting of sanctions. Building a nuclear weapon is not a key Iranian interest, and degrading Iran’s economy is not a key American interest. It is of course possible that the Iranians intend to continue a clandestine high-grade enrichment program, but they would be unlikely to succeed with the attention of all key intelligence agencies in the world focused on their activities. In addition to the bomb, they would need to build a reliable delivery vehicle. Its development would be even more difficult to conceal, and the consequences would be equally severe. On the other hand, the prospect of having sanctions lifted is enticing. All regimes place self-preservation at the top of their priorities, and the stability of the government in Teheran may be severely undermined if the sanctions remain in place. Annual inflation rate exceeds 50 percent, and unemployment is rampant, especially among the young. The $7 billion relief package is not going to make much difference to a nation of 80 million, and the vast majority of Iran’s approximately $100 billion in foreign exchange holdings are inaccessible or restricted by sanctions.

It is in the American interest to encourage the development of a regional balance-of-power system in the Middle East, whereby Persians and Arabs, Sunnis and Shias, would keep each other in check. That system requires Iran’s participation as an equal player. In the final settlement Iran’s demand that it should not be prevented from the legal use of nuclear technology for electricity generation and other peaceful purposes is likely to be accepted by the 5+1. Iran will remain only theoretically nuclear-capable, within an international supervision regime designed to prevent any sudden breakthrough. Israel and Saudi Arabia are unsurprisingly unhappy that America has not entered a risky imbroglio for the sake of their strategic interests, but neither will act unilaterally to alter that outcome.

Even if at some future date Iran does develop a nuclear weapon, that would not be the end of the world. The United States, Russia (previously the USSR), China, Great Britain, France, India, Pakistan, and Israel have possessed nuclear weapons for decades. None of them has ever been able to change the status quo in its favor by threatening to use the bomb, let alone by using it. The possession of nuclear weapons by one of the parties did not impact the outcome in Korea in 1953, or Suez in 1956, or prevent the two superpowers’ defeats, in Vietnam and Afghanistan respectively. It makes no difference to China’s stalled efforts to bring Taiwan under its control. South Africa had developed its own nuclear arsenal in the 1980s—it has been dismantled since—but this did not enhance its government’s ability to resist the winds of change in the early 1990’s. Ever since 1945, the political effect of a country’s possession of nuclear weapons has been to force its potential adversaries to exercise caution and to freeze the existing frontiers. There is no reason to think that Iran would be an exception to the rule.