Transcript for North Korea missile launch fails

We begin tonight with the intensifying tensions with north Korea and new concerns about the reach of their deadly weapons. That country's military muscle on display once again at a parade in Pyongyang showing off what may be missiles, sending a message to president Donald Trump. The unpredictable leader taking this show of force during a celebration of the 105th birthday of his grandfather, the country's founder. This as our global affairs correspondent got rare access to a key south Korean air base, shedding new light on the issues facing this rising conflict. And vice president Mike pence arriving in the region later tonight. ABC's Martha Raddatz leading us off tonight. Reporter: The massive military parade comes as tensions with the U.S. Are at the parade today, North Korea responding to statements like these from president Donald Trump. North Korea is a problem. The problem will be taken care of. Reporter: With a new warning, North Korea's second-most senior official saying Donald Trump is creating a war situation and North Korea is prepared for "All-out war" including a "Nuclear attack." So far, the underground nuclear tests that some analysts anticipated to coincide with the celebration of North Korea's most important patriotic day have not happened. But tonight, all eyes on the newest weapons in the reclusive nation's arsenal. Canisters large enough to hold what may be a new type of intercontinental ballistic missile and for the first time up close, submarine-launched missiles. The north Korean are trying to develop missiles that could reach the U.S. And already have weapons that could reach yap Japan and South Korea. So this is serious stuff. Yes, ma'am. This is your third set of blast doors here. Reporter: Just a few dozen miles from the dmz, the most militarized border in the world, we had a rare visit deep inside the u.s.'s san air base, one of the first lines of defense against North Korea. Here, U.S. Fighter jets take off to patrol the skies above and we saw up close patriot batteries, a missile defense system guarding against an attack from North Korea. Basically what a patriot does is it determines an inbound threat missile, we fire a patriot missile at it and it's a bullet on bullet scenario where the patriot missile hits the threat missile and destroys it. Reporter: One of the generals in charge of all U.S. Forces in Korea tells me the situation is extremely tense. And it's our preparedness that is our best deterrent. But we take this -- his threats and his developments very seriously. Reporter: And Tom, even though the north Koreans have yet to conduct that sixth underground nuclear test, the general told me it could happen any time. Tom. Martha Raddatz monitoring those developments tonight. Thank you. For more on North Korea's moves, let's bring in retired colonel Steve ganyard for more on that north Korean arsenal. You reviewed that video. What did you see in that parade that you found troubling? Several things, Tom. The first is those big canisters. It clearly signals North Korea's intent to build bigger, longer range missiles that eventually could hit the continental united States. Also the diversity of missiles. We saw not only land-based but submarine-launched missiles. Those missiles on trucks, it means they're road mobile, they can hide in forests, pop up and shoot before the U.S. Has a chance to react. Steve, adding to today's celebration and the tension with the U.S., some experts thought North Korea's leader, Kim Jong un, would have tested a nuclear weapon today. Well, Tom, he certainly has a flare for the dramatic, and so perhaps he's saving something for another day. Perhaps for a special greeting for vice president pence who comes to Seoul tomorrow. And that timing of course could be even more dangerous. All right. Steve, thanks so much. And much more from south Korea tomorrow on a special edition of "This week" Martha Raddatz anchoring from Seoul with an exclusive interview with president trump's top national security adviser H.R. Mcmaster.

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