There is a crisis in the Middle East you may not know much about. It's a bitter fight among American allies that has the potential to unravel the U.S.-led coalition that is battling ISIS and trying to contain Iran. At the center of the dispute is the tiny nation of Qatar, home to the busiest and most vital American air base in the region. On June 5th, Saudi Arabia, the United Arab Emirates, Egypt and Bahrain launched a suffocating economic and political blockade against Qatar, accusing the country of funding terrorism and cozying up to Iran. Qatar has denied and denounced the charges. The target of the nearly five-month-old siege is Qatar's 37-year-old emir, Sheikh Tamim bin Hamad Al Thani, who is now facing the challenge of saving his country.

Sheikh Tamim bin Hamad Al Thani, Qatar's emir, and 60 Minutes correspondent Charlie Rose CBS News

Qatar is per capita the richest nation on earth. Its wealth, reflected in the gleaming skyline of its capital Doha, is derived from the world's largest natural gas field. But the country's very existence was threatened on June 5th when the blockade was imposed by four countries that loom over Qatar, a country that is smaller than Connecticut and has a population of 3 million, only 300,000 of whom are native citizens. In an instant, Saudi Arabia closed Qatar's only land crossing. Not long ago hundreds of trucks a day flowed through this border post. Now, there is only dust. Sheikh Tamim, Qatar's young emir, had to steady a stunned and skittish nation.

Sheikh Tamim: More than 90 percent of our goods, food, medicine comes from the land. And this was blocked. Students were kicked out from those countries. Patients were kicked out from hospitals.

Charlie Rose: So Qataris who were in that country were ordered home?

Sheikh Tamim: Were ordered home, yes.

In an interview earlier this month in his office in Doha, the emir told us he didn't see the blockade coming.

Sheikh Tamim: Charlie, it was a shock. It was a shock because a few weeks before that, we were meeting, all of us together, in one room, including President Trump. And we were discussing terrorism, financing terrorism. And nobody brought any concern from those countries. Nobody told me anything.

Charlie Rose: So this is a meeting in Riyadh, Saudi Arabia. The president's there…

Sheikh Tamim: Exactly.

Charlie Rose: And no one suggested they had reason to launch an attack against you?

Sheikh Tamim: Nothing. It was actually the opposite. We were praising each other, laughing with each other. Discussing, you know, how to solve this terrorism that is a threat for the rest of the world.

Charlie Rose: What do you think this is about? Because this is a conflict that has as much power to disrupt the region as anything that's happened politically in a while. So why are they doing it? For what purpose?

Sheikh Tamim: They don't like our independence, the way how we are thinking, our vision for the region. We want freedom of speech for the people of the region. And they're not happy with that. And so they think that this is a threat to them.

"Our sovereignty is a red line. We don't accept anybody interfering our sovereignty."

Qatar is the non-conformist of the region, an upstart that often refuses to go along with Saudi Arabia and the United Arab Emirates. In the mid-nineties, Qatar started the satellite news channel Al Jazeera, which has been a major irritant to autocratic regimes across the Arab world, but the list of complaints goes deeper.

Charlie Rose: Here's what they are saying. That you're supporting terrorism. That you support the Muslim Brotherhood, which they believe is against them. You're too friendly with Iran. That Al Jazeera, which you own, stirs up trouble in the region. That you're financing Islamist groups in Syria. That you allow the Taliban and Hamas to operate out of Doha. And that you are playing too many sides. And that the time has come to stop it. That's what they are saying.

Sheikh Tamim: Charlie, Iran is our neighbor. And by the way, us as a country, we have lots of differences and foreign policies with Iran, more than them. But let me tell you one thing Charlie. When those countries, our brothers, blocked everything. Blocked medicine, blocked food, the only way for us to provide food and medicine for our people was through Iran. And when they talk about terrorism, absolutely not. We do not support terrorism.

In July, after a year of talks, Qatar finalized an agreement with the U.S. to combat terrorism financing. It didn't sway the blockading countries.

Charlie Rose: They're making demands of you. That you shut down Al Jazeera, that you give them your word that you're not supporting any Islamist groups. Are you gonna meet these demands?

Sheikh Tamim: Our sovereignty is a red line. We don't accept anybody interfering our sovereignty. When you tell me to close a channel like Al Jazeera, history will write one day in 50, 60 or 70 years how it changed the whole idea of free speech in the region.

Charlie Rose: So you're not gonna shut down Al Jazeera?

Sheikh Tamim: No, we're not gonna shut down Al Jazeera.

Doha, Qatar's capital city CBS News

Like Saudi Arabia, Qatar officially adheres to the ultra-strict form of Islam known as Wahabbism. Unlike Saudi Arabia, Qatar permits Christians to practice their faith in churches. Saudi women will only gain the right to drive next June, women in Qatar have been driving for decades. Politically, Qatar has also dismayed its neighbors by talking to friend - and foe.

Charlie Rose: This is what is at the core. You're different from them. And they have finally said to you, "You have to stop playing all sides because it threatens us and it competes with us.'

Sheikh Tamim: Actually, what they're saying in a very simple way, 'Give up your independence.'

The emir explained why one foe, the Taliban, was invited from Afghanistan to open an office in Qatar.

Sheikh Tamim: The reason why they came here, it's not because we asked them to come here, because other people…

Charlie Rose: Like the United States?

Sheikh Tamim: Yeah, yeah. America asked…

Charlie Rose: The United States wanted the Taliban here?

Sheikh Tamim: They wanted to have dialogue so they asked us if we can host them here and have the dialogue. So we hosted them here. This is the reason why they're here.

When Arab streets exploded across the region in 2011, Qatar openly backed the uprisings that eventually toppled longstanding dictators. The upheavals unnerved Saudi Arabia and the United Arab Emirates.

Sheikh Tamim: The difference between us and them during the Arab Spring is that we stood by the people.

Charlie Rose: And they stood by the regimes?

Sheikh Tamim: They stood by the regimes. It showed after that they stood by their regimes. Why did we stand by the people? Because they were asking for freedom, dignity. And I feel that we chose the right side when we stood by the people.

Qatar began punching above its weight under the emir's father, Sheikh Hamad. He was a visionary who took over the nation in 1995. Sheikh Hamad pushed to make his country relevant and indispensable. Qatar, a soccer lightweight, won the right to host the World Cup in 2022 in a surprising and controversial decision. The most strategic move came soon after 9/11 when the United States military pulled out of Saudi Arabia. Qatar offered the Americans a home.

Sheikh Tamim: We told them, 'Welcome to Doha. Welcome to Doha. Welcome to Qatar. We have a strategic partnership with you. And we want this to be very solid. So we're friends. So you're welcome to Qatar.

"I'm fearful that if anything happens, if any military act happens, this region'll be in chaos."

Qatar built Al Udeid Air Base to American specifications. 365 Days a year, 24/7, U.S. and allied aircraft take off from Qatar's desert to strike enemy targets in Afghanistan, Iraq and Syria. 10,000 Americans and coalition forces operate out of the sprawling air base. It may be why President Trump, after initially tweeting support of the blockade, now seems eager to end it.

Charlie Rose: You have heard that the president said, 'This cannot happen?'

Sheikh Tamim: I've heard that. I've heard that, 'This cannot continue. It should end.'

Charlie Rose: And 'We cannot tolerate an invasion from outside by our friends against another friend?'

Sheikh Tamim: He told me very clearly, 'I will not accept my friends fighting amongst themselves.'

Charlie Rose: So you were actually fearful of that?

Sheikh Tamim: I'm fearful that if anything happens, if any military act happens, this region'll be in chaos.

Charlie Rose: It is said that the president has asked you to come to Camp David. Have you accepted that invitation?

Sheikh Tamim: Yes. I had, I met with, with the president when I was in New York a few weeks ago…

Charlie Rose: For the United Nations…

Sheikh Tamim: For the United Nations. And the president showed that he is committed to find an end to this crisis. And yes, it is true, he, he suggested that we come. And I told him straightaway, 'Mr. President, we are very ready.' I've been asking for dialogue from day one.

Charlie Rose: And what did the other countries say?

Sheikh Tamim: It was supposed to be very soon this meeting. But I don't have any response…

On a visit to his former English speaking school, Sheikh Tamim told us he never expected to be emir. He wasn't in the line of succession. As a teenager, his ambition was to become the Arabic Boris Becker. Once his tennis dreams were dashed, he was another wealthy member of the royal family. Then, he says, one night his older brother Jassim, the heir apparent to their father, asked to see him.

60 Minutes correspondent Charlie Rose and Sheikh Tamim bin Hamad Al Thani, Qatar's emir CBS News

Sheikh Tamim: And he said, 'You, you are the best choice. And you are much better than me.' He said that. I remember. I was shocked. I said, 'Jassim, what are you talking about?'

Charlie Rose: That's the first time you thought, 'I may very well become emir.'

Sheikh Tamim: Yeah, I'll be the heir apparent.

Sheikh Tamim became the emir in 2013 at age 33 after his father abdicated. This current crisis has severely tested him. American diplomats tell 60 Minutes the emir has been calmly defiant, refusing to cave to the pressure from the blockading countries.

Charlie Rose: Do you believe that they want regime change?

Sheikh Tamim: Yes. They want, they want a regime change. It's... so obvious. History as well tells us, teaches us they tried to do that before, in 1996 after my father became the emir. So, and they made it also so obvious in the last couple of weeks.

Charlie Rose: What's happened in the last couple of weeks that makes this obvious?

Sheikh Tamim: Well, they've been talking in the media that this regime should be more suitable with its neighbors. And they mean us being followers to them, not being independent. This is what they mean and this is what they want.

Charlie Rose: Have they underestimated you?

Sheikh Tamim: I think they underestimated the Qatari people. I'm so proud of the people.

When the border was shut, there was a dairy shortage. But in three months entire farms rose from the desert. If the Cold War had its Berlin Airlift, the Gulf crisis has its bovine airlift. More than a thousand cows a month are imported by plane from California, Wisconsin and Washington state. The blockade forced Qatar to pursue new trade routes. Shipping has increased at its recently-opened, multi-billion dollar port. Since June, Qatar has had to dip into its abundant treasury, but expansion continues unabated, off into the hazy horizon. There's a mall just for kids, a national museum that will open next year. Work on the audacious World Cup stadiums, like Al-Bayt, which will be wrapped like a bedouin tent, proceeds around the clock - mostly on the backs of migrant laborers who toil in stifling temperatures. Across Qatar, a sense of urgency has galvanized the country to meet the current threat.

Construction in Doha, Qatar's capital city CBS News

Sheikh Tamim: Qatar after the 5th of June is not like Qatar before. We're proud of what we were. We're proud of our history. But after the 5th of June, it's different. We are stronger.

When he returned home from the United Nations last month, the emir was met by an outpouring of support, not only at the airport, but on Doha's Corniche. It was as if he had earned the country's confidence. Everywhere you look, there are murals of the emir, icons that have decorated Doha since the start of the blockade.

Charlie Rose: How will this end?

Sheikh Tamim: We want it to end. Believe me, Charlie, we want it to end. But nothing is gonna be above our dignity, our sovereignty. But we want it to end. I always say that. If they gonna walk one meters toward me, I'm willing to walk 10,000 miles towards them.

Produced by Draggan Mihailovich. Laura Dodd, associate producer.