Transcript for How US, Allies Reached 'Historic' Iran Nuclear Deal
Tonight an historic agreement with wufb America's staunchest'd Ver Sierras. Iranian leaders agreeing to give unprecedented access to international nuclear weapons inspectors. In exchange for easing economic sanctions against the isolated country. If Iran cheats, says president Obama, the world will know about it. How's the plan being received? For the moment, with a lot of celebrating. It's ABC's chief foreign correspondent terry Moran. Reporter: Good evening, juju. The deadlines came and went here. The negotiators, some of them, came and went. But those who stuck it out emerged after several marathon sessions to announce a breakthrough. In the words of secretary of state Kerry, they have opened a window of possibility for a deal that is hoped will bring Iran's nuclear ambitions under strict international control. On the streets of Tehran tonight, there was joy. To so many of the people of Iran, so long cut off from the world economy, this deal is about more than nuclear technology and international relations, it's about hope. In luzon, Switzerland, where negotiators worked marathon sessions to get this deal done, there was a sense of relief more than anything else. For secretary of state John Kerry, today was a personal achievement. But he acknowledges there's still a lot of work to do, and the deal is far from done. Could this whole thing still fall apart in the next few months will you hammer out the -- Of course it could. What's the chances of it getting all the way? I don't have any way to make that prediction. 50/50? I'm not going to play that. This is a way of making the world safer. Reporter: But how? Under today's agreement, Iran's nuclear programs will come under strict international controls and some of them will be rolled back. In exchange for economic relief, lifting those crippling sanctions on Iran. Iran will also get to keep much nuclear technology and research, as long as it can be verified that it will be used for civilian purposes. Electric power generation. Medical technology and the like. President Obama in the rose garden insisting he drove a tough bargain. This framework would cut off every pathway that Iran could take to develop a nuclear weapon. This deal is not based on trust. It's based on unprecedented verification. Reporter: Critics say the agreement makes the world more dangerous. This deal is going to threaten America's national security interests and it's going to lead to a nuclear arms race. Reporter: Republicans also say the president was desperate for a deal to burnish his legacy. There's a sense that president Obama wanted this deal more than Iran did. And that weakened your position as a negotiator. Not on your life. President Obama on several occasions could not have been clearer about my instructions to walk away if X, Y or Z doesn't happen. Reporter: Okay, enough with the politicians. Let's hear from the people, from those with a special stake in the outcome here. This was a big deal. It's transformative. Reporter: This evening we brought together five ir iranian-american professionals to talk about what this deal means to them. I think it's a very hopeful and exciting moment. Because this is an opportunity for people that have been suppressed for so long to kind of have a voice that's going to help the economy in Iran. And this is going to help the welfare and economy of the Iranian people. From a selfish and convenience point, hopefully it means more flights to Iran by a lot of the airlines because of the sanctions pulled out and canceled flights, it's difficult to get there from the U.S. There's this dehumanization of Iran as a country or a government, as you name it, supporter of terrorism -- It's a complex country. Just as the United States is. Reporter: They're hoping today will mark a change in the way Americans view Iran and Iranians like themselves. For these iranian-americans, for those people on the streets in Tehran, for all those in both countries, this day of hope is shadowed by a long, dark history. 1979. Iranians rise up in self lose head by the ayatollah khomenei, a fierce religious leader and critic of the U.S. Then in November that year, Iranian students stormed the American embassy and take 52 U.S. Diplomats hostage for 444 days. "Nightline" got its start covering the crisis, which riveted and infuriated the country. Again today, Iran is the major story. Reporter: The hostage crisis led to decades of hostility between the U.S. And Iran. No diplomatic relations at all between the countries. By 2002, president George W. Bush lumped in Iran in with North Korea and Iraq in -- An axis of evil arming to threaten the peace of the world. Reporter: So the die was cast. Inside ever raun, life was never the same after the revolution. I was 8 years old at the time of the revolution in 1979. And my life as a girl from the middle class family in Iran was affected by the revolution in very profound ways. Reporter: She was born in Iran and now lives in the U.S. As a young girl I had to wear a head scarf. I could no longer do a lot of things I could do. Islamists believed women could not wear swimming suits. Even if they were as young as 8 years old. And swim in public. Reporter: A "New York times" correspondent, show fled the country with her family in 2009 after the regime crushed popular protests and threatened her directly. Today, she felt close to the home she has lost. Today was one of the happiest days of my life. This is the first time that Iran and the United States managed to end one of the biggest crises through diplomatic solutions. Reporter: But is that hope justified? And can it be the two countries with so much bad blood between them could trust each other, work together? Iran is a country that has been at the center of the world for a very long time, a 3,000-year-old history. The population yearns to reconnect with the world. Reporter: So much hard work ahead still to see if the hope there and here can change history. For "Nightline," I'm terry Moran in lieu Zahn, Switzerland.
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