North Korea’s military may be armed with obsolete conventional weapons, but at 1.2 million men, it poses a very real threat to its neighbor and nemisis to the south.

Equipped with 20,000 artillery pieces, 1,000 short- and medium-range missiles, 70 submarines, more than 400 patrol/missile boats and 563 combat aircraft, the Hermit Kingdom's forces are poised to do maximum damage in a sneak attack against South Korea.

Its 10 plutonium-based nuclear warheads and evolving missile technology exists to project power beyond the peninsula, but there is little doubt that the rogue nation's first target should it declare war will be South Korea.

A strike against Seoul would be devastating. At 25 million people, it is the most densely populated city in the world. Seoul is just 30 miles from the demilitarized zone, the contested boundary between North and South which are still technically at war and restrained only by an armistice in place since 1953.

Pyongyang has an estimated 4,000 artillery guns and rockets placed on the heights north of Seoul just across the DMZ, many of them on rails so they can be moved into place in time to avoid detection.

Adm. Harry Harris, commander of U.S. forces in the Pacific, said America needs to wield “credible combat power all the time” to face whatever threats come out of North Korea, “I think the lack of a strong, credible combat deterrence is actually an encouragement to Kim Jong Un to do things that are provocative or dangerous or both… that threaten those millions who live in Seoul.”

The U.S. military regularly conducts combat simulations with experts from the private sector and the Pentagon to determine the outcomes of a North Korean attack on the South.

Former Army Intelligence Officer Michael Pregent served in rapid response units that would deploy to Korea in the event of a conflict. Now a fellow at the Hudson Institute, he took part in war games that simulated a North Korean offensive against South Korea when he was with the 101st and 82nd Airborne Divisions.

“The first wave is the most destructive one,” said Pregent.

They have a “shock capacity” that includes raining down artillery shells and rockets on population centers. Experts say the North Koreans could attack Japan with warheads mounted on medium-range rockets. Harris was asked about possible nerve gas or chemical weapons attacks on its neighbors.

“I think that's part of the readiness calculus that we have to go through when we consider the threat from North Korea,” Harris told the Senate Armed Services Committee.

Hundreds of thousands of troops backed by armored vehicles would then be expected to swarm across the border, hoping to take advantage of the brief window of surprise to force a conclusion to the war practically before it started, and a ceasefire that would lead, presumably in the mind of Kim Jong-Un, to reunification.

According to Pregent, who took part in the war games, some of the next phase would be predictable, some of it might be surprising to lay observers.

“The artillery that fire first would be destroyed” by U.S. and South Korean air power and counter-artillery, then “there would be a second wave of North Korean artillery, and that would be destroyed too. All that would have caused havoc, of course,” said Pregent.

North Korea’s “military first” policy is intended to blunt the effect of persistent civilian food and fuel shortages on its armed forces. A South Korean lawmaker has asserted that North Korea has about a million tons of wartime food provisions. Enough, he claimed, to feed the million man army for 500 days.

But one thing that Pregent says Kim Jong Un must be painfully aware of is the logistical problem facing his ground forces.

“The regime fears desertion once their forces cross the DMZ,” said Pregent. “They can’t supply their troops with food, fuel, clothes, and ammunition. Every war game that I’ve ever been part of, the North Koreans run out of water, food and ammo.”

Pregent imagines the psychological impact on even the most hardened, elite North Korean shock troops once they cross from a nation that doesn’t even have lights on most nights, into a 21st century economic powerhouse.

“How do you stop a million-man force? You don’t, unless they stop themselves sometime between day 3 and day 7,” he said.

“The psychology of the North Korean shock troops, their special operators, is they’ve been told they are the best in the world. But the fact is their night vision is 20 years old, their weapons have a tendency to jam, and their boots are worn out. What happens when they see they’ve been lied to all their lives? Do they simply look at this as an opportunity to drop their weapons in awe of what doesn't exist in the North?”

“This is how closeted these guys are,” said Pregent, “the mere presence of a food stand bursting with goods on the side of the road would blow them away, not to mention ipads and iphones.”

Democrats in successive House and Senate Armed Service Committee hearings this week pressed Harris on the weakness of the North, and whether President Trump was provoking Pyongyang with our B1 and B52 missions in the region and the deployment of a powerful aircraft carrier battle group as well as a guided missile nuclear submarine, the USS Michigan.

“If you are a weak country, or you have a weak military, then I think that encourages adventurism and puts us in a place with countries like North Korea that we wouldn’t want to be in if we had a choice,” Harris told Rep. Susan Davis, D-Calif. “Credible combat power I believe has the effect of ameliorating Kim Jong Un’s worst impulses.”

Admiral Harris explained to Sen. Elizabeth Warren (D-MA) that if the United States allows North Korea to overcome its inherent weaknesses with a nuclear tipped intercontinental ballistic missile aimed at the United States, “then we're going to be in a position to be blackmailed by Kim Jong-Un and I think that's probably a worse place to be. I think that we'll all agree that everything that's been done up to this point has not worked in deterring Kim Jong-Un. So we must stop that, somehow.”

Asked whether the United States military can take out North Korea’s artillery aimed at Seoul with a pre-emptive strike, Harris said, “It depends on the level of the pre-emptive strike.”