Pentagon: N. Korea Missile Advances 'In Line' with Kim's Desire to Strike U.S.

"Although North Korea is unlikely to attack on a scale that it assesses would risk the survival of its government by inviting overwhelming counterattacks by the ROK or the United States, we do not know how North Korea calculates this threshold of behavior," the report continues. "North Korea’s use of small-scale attacks and provocative acts leaves much room for miscalculation that could spiral into a larger conflict."

Pyongyang is making "some effort" to upgrade its conventional forces as well as expand its nuclear capability, and the Pentagon expects missile tests in defiance of UN sanctions will continue.

The intelligence on emerging weapons capabilities is largely gleaned by what is put on display at military parades in the nation's capital.

With the past couple of years this has included new tanks, artillery, and infantry weapons, updating the Soviet-era stock that had been propping up the ground forces. In all, the Pentagon estimates Pyongyang has 4,100 tanks, 2,100 armored vehicles, 5,100 multiple rocket launchers, and 8,500 field artillery, mostly concentrated in the south. The country has nearly a million military personnel in the ground forces at maximum strength.

The North Korean Air Force has more than 1,300 aircraft, with the most recent "surreptitiously purchased used Kazakh MiG-21." In 2010, Pyongyang dispelled a new vertical mobile surface-to-air missile launcher with radar that bears a striking resemblance to Russian and Chinese equipment. Its Navy has patrol combatants, amphibious landing craft, and mini-submarines like the one that sank the Cheonan.

Special operations forces -- a "vital tool tool for asymmetric coercion" -- and an "ambitious" ballistic missile unit round out the military.

Advances seen in ballistic missile delivery systems, including improvements to the Taepo Dong-2 missile system with a range greater than 3,400 miles, and nuclear developments "are in line with North Korea's stated objective of being able to strike the U.S. homeland."

"North Korea followed its February 12, 2013 nuclear test with a campaign of media releases and authoritative public announcements reaffirming its need to counter perceived U.S. 'hostility' with nuclear-armed ICBMs," states the report. "North Korea will move closer to this goal, as well as increase the threat it poses to U.S. forces and Allies in the region, if it continues testing and devoting scarce regime resources to these programs. The pace of its progress will depend, in part, on how many resources it can dedicate to these efforts and how often it conducts tests."

The Pentagon also found North Korea "probably" has cyberwarfare capabilities, something at which their friends the Chinese are particularly adept. North Korea has been blamed for a range of cyberattacks in the past few years. "As a result of North Korea’s historical isolation from outside communications and influence, it is likely to employ Internet infrastructure from third-party nations."

The country's "world-wide network" of arms sales includes regular customers Iran, Syria, and Burma. Its biological warfare capability is "potentially robust" and its probable "longstanding" chemical weapons program is thought to have the capability to produce and stockpile "nerve, blister, blood, and choking agents" -- and sell them to the highest bidder.