Transcript for How the Iran Nuclear Deal Hits Home in the US
groundbreaking nuclear agreement with Iran, after weeks of grueling negotiations. In Tehran, some are celebrating in the streets, but elsewhere across the globe and here at home, critics want to kill the deal. Terry Moran with the implications we'll soon CICI from congress to our gas pumps. Reporter: This is the party they've been waiting for in Tehran. The sights and sounds of a people with a new future in front of them, because of this. This moment has been a long time coming. And we have worked very hard to get here. Reporter: After grueling negotiations, a deal between Iran and the United States and its allies, the land of the ayatollahs, doing a deal with the government they call the great Satan. This deal offers an opportunity to move in a Fu direction. Reporter: The basic outline of the deal is simple. Iran will voluntarily cut back most of its nuclear activities for the most decade or more and submit to constant inspections. In return, they will lift the sanctions on their economy. Netanyahu called it a stunning, historic mistake. It may be the worse diplomatic agreement in the H history of the United States. Reporter: And by the candidates hoping to replace Obama in the white house. But secretary of state Kerry defended the deal and challenged critics. So what's the alternative? The alternative is to go to war immediately? Bomb them? Sanction them further? Wait, you can't sanction them further. Reporter: Tonight my colleague Martha Raddatz is out on the streets. Celebrations have been breaking out tonight, celebrating the historic deal between America, its partners and Iran. All of these people know that those punishing sanctions will be lifted within the next couple of months, and many civilians, many of these people have suffered under those sanctions. Reporter: These scenes so unlike the images that defined u.s./iran relations for 36 years. The 1979 hostage crisis. In a revolution led by the fiery ayatollah khomeini, Americans were taken hostage for 444 days. "Nightline" got its start covering that 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. By 2002, president George W. Bush lumped Iran in with north Korea and Iraq in -- An axis of evil, to threaten the peace of the world. Reporter: Today president Obama closed that chapter. It can bring about real and meaningful change. Reporter: This is a society in the process of change, and many are eager to speed that up. Very good deal between Iran and other countries. I think it some other countries are not very happy about this, but I think it would be a good chance for Iranians. Reporter: Martha Raddatz describes Iran as vibrant, chaotic and divided. From the chic shopping malls where westernized young well push the limits on the legal requirement to cover their hair. Many years ago you would have been arrested. Yeah. Reporter: To the mass marches she witnessed just days ago with the faithful shouting "Death to America", and any nuclear deal with it. Obama will back John Kerry. Reporter: It is a nation in a tug-of-war. 70% of Iranians are under the age of 35, born after the revolution. Its emboldened youth population battling against those who cling to the past. What is the one thing you wish would change here? I have problem with scars. And I have problem with going out. Reporter: And for Iranian Americans living in Los Angeles, today's deal creating an opportunity to talk and reflect on their complicated heritage. Growing up, you had your American side and your Iranian side. It can really make a big difference. Reporter: Amy malik is a lecturer at ucla. Many of her students and friends and families back in Iran share her cautious optimism. Today we were sharing a bunch of stuff. It's exciting. I think it's a pinprick of a larger age of what diplomacy should be looking like. Reporter: They're also hopeful a deal like this will change perceptions here in the United States. I think we need to end some of the stereotypes that occur with Iranians in America. Reporter: These kinds of changes take time, but already the deal has impacted global markets. Experts are redibting gas prices will drop, first by only a few cents, but some predict prices as low as $2 per gallon by December of this year. But the changes here at home are likely to pale to those seen across Iran where tonight there is hope in the air. For "Nightline," I'm terry Moran in Vienna.
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