Transcript for US, South Korea respond to North Korea's ICBM launch

We'll begin with breaking news around the world. Tensions high over North Korea. Overnight the U.S. And south Korea responded to the north Korean missile launch with a show of force launching our own missiles into the sea. It was a long-range intercontinental ballistic missile that they launched. President trump leaves for his g20summit. He'll stop in Poland ahead of that and he'll deliver a major speech there tomorrow. On Friday his first meeting with Vladimir Putin. The big question, will trump confront Putin over Russian interference in our presidential election? We'll have more on that. First the escalating crisis with North Korea and our chief global affairs anchor Martha Raddatz. Good morning, Martha. Reporter: Good morning, George. A very strong statement this morning from the top American commander in South Korea saying that self-restraint is the only thing keeping the U.S. And south Korea from going to war with North Korea after its breakthrough missile launch. Overnight, the U.S. And south Korea responding with a show of military power. A volley of short-range missiles fired into the waters off the east coast of the Korean peninsula. That coming just hours after North Korea successfully test launched a two-stage intercontinental ballistic missile that could potentially reach Alaska. A major breakthrough for a country that has long sought a missile to directly threaten the U.S. The country's leader, Kim Jong-un, there to oversee the July 4th launch calling it a package of gifts for America on its end penindependence day. It reached an altitude of 1700 miles, likely so it did not overfly Japan or Russia. But if the north Koreans angled the trajectory for distance instead of height experts say the missile could travel well over 4,000 miles, not just in range of Alaska but very close to the U.S. Mainland. Celebrated as a success by a north Korean news reader and applauded by the public, the missile called the final step in creating a confident, powerful nuclear state that can strike anywhere on Earth. In reaction, Russia and China proposing a moratorium on north Korea's nuclear tests and a halt to U.S. And south Korean large-scale military exercises. Proposals which have been outright rejected. Just days ago president trump warning Kim Jong-un to stand down. The era of strategic patience with the north Korean regime has failed. Many years and it's failed. And, frankly, that patience is over. Reporter: Before he took office, president trump warned that he would not allow north Korea to develop a nuclear weapon capable of reaching the U.S. They have still not perfected that but they have now come one big step closer and it is unclear, George, what he can do about it. Okay, Martha, thanks very much. Let's get more from our military analyst Stephen ganyard. Let's begin with that north Korean missile test. We know it's an icbm and it could reach potentially the United States but to have a missile be able to strike the United States they need to perfect a nuclear warhead. One that could survive re-entry into the atmosphere. That's right, George. We know -- we've seen a M miniaturized nuke but the real trick have that nuke on that rocket survive the high heat of re-entry. We know they're working on this. We saw they actually addressed the warhead temperatures so when does this happen? A year, two year, maybe three but we need to remember we have consistently underestimated the progress of the north Koreans. They've been moving relatively quickly and we have relatively few options to stop it. Right now the U.S. Will go to the U.N. They'll talk to the U.N. The U.N. Hasn't been terribly helpful in terms of saxes so this will be a unilateral effort by the U.S. The department of defense will have to play defense but the real offense here is going to be the U.S. Department of treasury imposing sanctions on north Korean illicit activities. Our missile test overnight provocative as well. The general in charge in south Korea says this was designed to be a precision strike at enemy leadership. George, first thing if you look at, why would the U.S. Launch these short-range missiles in response? General brooks' comment was very clear. This was a demonstration of precision fires targeted at the north Korean leadership. Kim Jong-un needs to remember that he is target number one in the event of hostilities. Stephen ganyard, thanks very much. Amy.

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