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(NECN/NBC News: Jim Miklaszewski) - The US is bolstering its nuclear missile defenses in Alaska and in Japan because of the threat mostly from the new North Korean leader but also from Iran.
There are actually sources telling the US that they believe the North Korean nuclear program is further along than they first thought. And their nuclear weapons are in the hands of an untested 28-year-old leader.
North Korean leader Kim Jung Un reviewed his troops during military exercises Friday, but at the Pentagon, defense secretary Chuck Hagel warned it's North Korea's long-range missiles that have sounded the alarm.
“North Korea in particular has recently made advances in its capabilities and is engaged in a series of of irresponsible and reckless provocation," Hagel said.
To counter the growing threat from North Korea, the military will bolster the missile defense system in Alaska by 50 percent, adding 14 interceptor missiles at Fort Greely designed to intercept and destroy ballistic missiles aimed at the continental US.
The US military will also install an additional high-power radar in Japan to improve early warning capabilities.
But why the deep concern now?
Unbelievably, it ramped up last April during a military parade through the streets of Pyongyang.
US intelligence was shocked to see what appeared to be long-range ballistic missiles that can be fired from mobile launchers with the capability of reaching the US with a nuclear warhead.
"Obviously without getting into intelligence aspects we watch this evolving threat very, very closely," Adm. James Winnefeld said.
This latest threat emerged as North Korea launched a satellite into space orbit last December and conducted a successful underground nuclear test last month
"They still have a couple of technological hurdles but this is not a long term threat, this is a near term threat," said Victor Cha of Georgetown University.
Just recently, North Korea publicly threatened to launch as preemptive nuclear strikes against the U.S.
As the US strengthens its missiles defenses, King Jung Un was personally warned, don’t even think about it.
"We believe that this young lad ought to be deterred by that and if he's not we'll be ready," Winnefeld said.
It'll still take two to three years before the entire missile defense system in Alaska is up and running
and the $1 billion dollars to pay for it won't show up in the shrinking Pentagon budget until next year.