Fox News reports that Japan lies only about 620 miles to the east of North Korea, which has conducted numerous missile tests this year.
The country has threatened nuclear attacks against the US and its allies as well as a missile strike on Guam.
"On the North Korean side", he says, "there are differences of specificity".
While tensions with North Korea have taken a bite out of the stock market, defense stocks are benefiting.
"You see these terrible headlines that's terrifying and freaks everybody out", Wachtel said."The most rational of thinkers will read a headline and think they'll have to hide under a bed because the world is going to explode soon".
If Japan or the United States shoots down the missiles, North Korea could see it as an escalation, prompting a military response.
"Missile defense has taken on a mythical quality right now", Collina said.
And for the past year, he said, he's been trying to urge his colleagues to devote more federal attention and spending to missile defense.More news: Can US Attack North Korea and Claim 'Self Defense'?
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Missile defense is an attractive but tricky strategy in dealing with missile threats. If the USA or Japan successfully intercept the missile it could be taken as an act of war, prompting further military response.
But Sullivan said the US needs "belts and suspenders" when it comes to missile defense - redundancy.
The revelation that North Korea had miniaturized its nuclear weapons to fit atop an ICBM was a "surprise". "We are going to be increasing the anti-missiles by a substantial amount of billions of dollars". The same system is now set up in Guam, a USA territory in the South Pacific that has emerged as a potential target for Kim.
"If one of those options is a pre-emptive war on the Korean Peninsula launched by the US, that would require authorization from Congress. Article I of the Constitution, in my view, makes this clear", Sullivan said.
President Donald Trump on Thursday expressed disappointment with his administration's missile defense budget, pledging to ramp up spending on the military's efforts to intercept incoming missiles from North Korea and elsewhere by billions of dollars. "I think some failure is possible and perhaps expected, as they haven't yet been tested in fully operationally realistic conditions". Last month, the U.S. Missile Defense Agency announced that its THAAD system in Kodiak, Alaska, successfully intercepted an intermediate-range ballistic missile for the first time in a test.
She pointed to a review of the nation's ballistic missile defense that is underway at the Pentagon, and said that is likely to provide "a pathway forward to further missile defense improvements".
Reports suggest that Kim Jong-un does have some form of nuclear bomb, but there is disagreement over whether the country has managed to make warheads small enough to fit on its missiles.