Story highlights The US says North Korea now poses a "practical" rather than "theoretical" threat

North Korea no longer cares if the world sees its tests as failures

Washington (CNN) The US government is increasingly concerned that advances in North Korea's weapons program have dramatically decreased the warning time for a nuclear attack on America or its allies, according to US officials.

The regime's aggressive testing of medium- and long-range missiles -- as well as its nuclear testing -- makes North Korea now a "practical" threat and no longer a "theoretical" threat, in the words of one US official familiar with the latest US intelligence thinking.

Significantly, North Korea no longer cares if the world sees its test failures, according to the latest analyses, allowing Pyongyang to more openly, aggressively and repeatedly test all of the key components needed for an attack.

As a result, the regime has the ability to hold the US and allies "at risk" with nuclear weapons, the US official said.

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