How real is the prospect of a nuclear deal with Iran? (CBS News) Working with Iran to resolve international concerns about the country's disputed nuclear activities might finally be an achievable goal for the United States, former President Jimmy Carter's National Security Adviser Zbigniew Brzezinski said Sunday on "Face the Nation." "We have to take into account the fact that this is a significant historical nation that has lasted for 3,000 years, has a glorious history," he said. It's not a crazy nation, not suicidal. ..."Think of the Soviet Union," Brzezinski continued. The Soviet Union was led by leadership that killed millions of people. It acquired nuclear weapons. It was threatening us. We managed to negotiate with it, we managed to have arrangements to stabilize the nuclear arms race, minimize the prospects of war. We can do it with the Iranians, absolutely, provided we don't listen to advice that is extreme and pathological. A phone call Friday between President Obama and Iranian President Hasan Rouhani marked the end of a 34-year silence between leaders of the two nations. During the 15-minute conversation, Rouhani - eager to ease crippling sanctions as quickly as possible - reportedly reiterated his desire to revive stalled talks with world powers to curb Iran's nuclear program. "If things go wrong in the Middle East, it's going to be a massive globally significant crisis," Brzezinski said. Probably the gravest since the Cuban crisis in the sense that its potential consequences will not be an atomic war, but massive economic and political disruption in a very important part of the world. This is in our interest to avoid. The "good news," he went on, is other world powers - even Russia - realize what's at stake, especially in Syria. "We have a putative coalition for peace," Brzezinski said. If we stick with it we might be able to preserve some sort of stability in the region by accommodating with the Iranians, by finding some sort of compromise formula for Syria, and for pushing the Israeli-Palestinian peace process forward. But all three things have to happen. CBS News foreign correspondent Clarissa Ward argued later on the program that that is a tall order. "There's reason for cautious optimism, but it's way too early to say," Ward said, adding that Rouhani is "not actually the boss;" Supreme Leader Ali Khamenei is. A better idea of how seriously the United States can take Rouhani's overture will come Oct. 15, when Iranians will submit their formal proposal, CBS News State Department correspondent Margaret Brennan said. There is still some hope among U.S. negotiators, who, according to Brenna, "said [last] week the Iranians did something they've never done - they walked in with a time table; they walked in with ideas."