Transcript for Ganyard after failed N. Korea missile launch: 'We can't be too complacent'

Reporter: We're back now live in Seoul. I'm joined by ABC news contributor colonel Steve ganyard, a retired Marine Corps fighter pilot and former deputy assistant secretary of state. Talk to us about the failed missile launch first. What do we know about that missile? Mgts it will take us awhile to figure out what kind of missile it was. Because it blew up so quickly after launch, we're not going to have much radar telemetry data. It will take awhile to figure out what a it was. It shows they're determined to perfect the missiles and develop a long-range missile capability. A real concern from this weekend is the parade. And the missiles that we spotted in the parade. We don't know if they're real. They appeared to be long-range missiles. Lots of concerning things out of the parade. The first is the size of the mizles. Bigger size. Means longer range. Better chance of getting all the way to the United States. The diversity of missiles that we saw. Not just land-based. Sea based. Submarine launched missiles. Some of them looked like a df-31. A sophisticated Chinese missile. Lots of questions coming out of that. Lots of things to worry about. Real takeaway is range. For decades, presidents, Republican and Democrat IX, have been able to kick the can down the road with North Korea because there's never been an ability to reach the united States. In that ma raid, those missiles, theoretically, could reach the United States. That's why president trump feels the need to take this on here and now. They're still expecting to launch the underground nuclear test. Is there anything to be done to stop them there doing that? There are a couple of options. One kinetic. One nonkinetic. There's a bigger bomb in the U.S. Inventory by weight. 30,000 mounds. It's called a M.O.P. Massive ordnance penetrator. It is able to take out underground binkers. That would be the kin etic option. There's a high-powered microwave. It would send an intense burst of elect trromagnetic energy. Nobody gets hurt. Everything gets disable period. The president has a new arrow in his quiver. Both kinetic and nonkinetic options. Steve, what do you think the reaction would be from north Korea if there was a preemptive strike? They've been quite clear. If there is any military action on north Korean soil, they will retaliate in some way. Lit occur on south Korean soil or at Japan. Which means we need to coordinate closely with our closest allies in the region before thinking about any kind of military action. Steve, very quickly. Our intelligence in North Korea is pretty bad. Why is that? We have very little human intelligence on the ground. It's a closed, stalinist society. Yesterday was similar to when we would wait for the may day parades to know what the soviet union was thinking and doing. This will continue to bedevil us. Thank you, Steve. President trump faces major decisions when it comes to

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