DAVID GREENE, HOST:
A pretty ominous-sounding warning from North Korea this morning. State media there warned the United States of a super mighty preemptive strike. This was in reaction to Secretary of State Rex Tillerson saying the U.S. wants to keep pressuring North Korea to abandon its nuclear program. So what could North Korea actually do to threaten us? Well, the country's ballistic missile program has emerged as one of the toughest early challenges for President Trump.
The North's most recent attempt to launch a missile fizzled. But the Pentagon says North Korea learns as much from its failures as it does from its successes and that the country's on its way to being able to put a nuclear weapon atop a missile that could someday threaten the United States. For more, I asked NPR national security editor Phil Ewing about the actual danger at this point from North Korea.
PHIL EWING, BYLINE: So the danger is we know the North Koreans have ballistic missiles. They've shot them into the ocean and demonstrated a lot of new advances in that way. And we know they have nuclear weapons. They've detonated a number of bombs below ground in the past few years. The issue is will they be able to build a nuclear weapon small enough to fit on top of one of those missiles to be able to threaten their neighbors - South Korea or Japan - or potentially even one day hit the United States?
We don't know if they're there yet or not. The Pentagon says it has to assume they're building toward that capability. And that's why the generals and admirals, especially in the Pacific, pay so much attention to this danger.
GREENE: But just to be clear that they have long-range missiles. I mean, something could hit the United States, not nuclear we don't think at this point. But, I mean, they could, you know, damage a U.S. city and cause some destruction.
EWING: That's the danger. And out in the open source, those of us in the civilian world don't have perfect information about what the Pentagon knows but they've demonstrated a lot of launches. They've demonstrated a lot of weapons. And you never know what they aren't showing, what they don't put in those parades you see sometimes on TV.
GREENE: OK. So the U.S. military is testing some ways to shoot these North Korean missiles out of the sky, right?
EWING: That's right. There's a whole U.S. missile defense system that's set up around the Pacific to try to defeat this threat. There are radars and missiles set up in South Korea and Japan and Guam and Alaska and California. There are Navy ships at sea in the Pacific Ocean that have sensors and missiles that they hope can try to shoot down a missile in a crisis scenario.
And in the next few weeks, the U.S. is expected to test at least two of these, one from a Navy ship at sea and one from a base in California. The goal is you want to develop a system that can see a launch from North Korea and shoot something that can hit it before it gets to the United States in a nightmare scenario. And they still may be a ways from doing that because the test record is not 100 percent.
GREENE: OK. So these things have been tested and they've not always gone so well.
EWING: That's right. They have hit some targets in some tests. But sometimes the missiles break or sometimes the test doesn't go the way the Pentagon wants it to. And so when U.S. policymakers, President Trump and before him President Obama are looking at this, they don't know if they have full 100 percent confidence that if the North were to launch a missile in a nightmare scenario, the U.S. would actually be able to hit it and stop it.
GREENE: And, Phil, let me just ask you this. I mean, you mentioned that these tests involve some ships at sea. President Trump right before the North's expected test not so many days ago announced that he was sending an aircraft carrier fleet towards the North. How does that all fit into this?
EWING: That's right. The Navy said the USS Carl Vinson Strike Group would cancel a visit to Australia and sail north instead. And it may eventually do that, although, in fact, the ships sailed south instead of north, they're taking their time with some exercises a thousand miles away from North Korea. But they will eventually sail there. And the Navy said Wednesday that its deployment has been extended by another 30 days to make that happen.
GREENE: Oh, so if the president left an impression that he was going to have an aircraft carrier fleet close to the North when this test happened a few days ago, that impression was not actually accurate?
EWING: That's correct. It'll be a while before the ships actually get up there.
GREENE: OK. NPR national security editor Phil Ewing, thanks.
EWING: Thank you.
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