Hans Kristensen: Each bomber can carry 20 cruise missiles a maximum of them so we’re talking about potentially 80 cruise missiles that could have been launched against targets inside Russia at this particular time.

Using the cruise missiles range of 1500 miles, Kristensen plotted his own hypothetical lines showing how far they could potentially reach into Russia.

David Martin: And the end points of those red lines?

Hans Kristensen: Yes, each of them go to a facility in Russia that could be a potential target for nuclear weapons.

David Martin: The Russians would look at that and see it as a dry run for an attack on targets inside Russia.

Richard Clark: I guess they can draw the conclusions that they need to draw.

David Martin: Eighty cruise missiles in your face.

Richard Clark: It’s a lot of fire power.

David Martin: Was that the message?

Richard Clark: That’s a message for sure.

The last time American nuclear bombers flew a mission like that was during the Cold War.

Richard Clark: This was a significant exercise for us. We’re training the way we might have to fight.

The president is due to consult his principal national security officials in October on which, if any, of the options are still feasible in the time left before he leaves office.

Some more radical options, like changing the US nuclear posture to rule out first use of nuclear arms in a conflict and taking some of the nation’s intercontinental ballistic missiles off hair-trigger alert, have faced such strong opposition from allies abroad and the Pentagon that they are no longer being seriously considered.

The North Koreans know what they are doing. They have now conducted five nuclear tests, which is actually quite a lot. (Oh, by the way, take a look at all the tunneling at the North Korean nuclear test site. They plan a lot more tests.)

That means we don’t really know how big North Korea’s nuclear arsenal is, or will be once the “standardized” warheads are deployed to the missile forces. But its not a small number, and certainly not just a handful. It’s a nuclear force, one that poses a threat to South Korea, Japan, and U.S. forces in the region. And it’s likely to keep growing. If we do nothing, I suspect it will grow in number, grow to threaten the continental United States, and eventually grow to include very powerful staged-thermonuclear weapons. And all this is going to happen sooner that you think.

It is hard to escape the conclusion that North Korea is preparing to deploy a force of nuclear-armed missiles. During Kim Jong-un’s time in power, North Korea has created a new “Strategic Rocket Force,” has dramatically increased the pace of missile testing, and begun to conduct operationally realistic tests including night-launches, salvo launches and openly practicing scenarios such as striking ports to prevent U.S. forces from coming to the aid of South Korea. The announcement of a standardized warhead appears to be another step in this direction.

It may be time to reassess what we imagine Kim Jong-un and the North Korean leadership think about nuclear weapons. While there is widespread agreement that North Korean leaders see nuclear weapons as a way to deter a U.S. invasion, North Korean statements also make clear that the role of nuclear weapons is to repel an invasion if deterrence should fail. The deployment of a significant nuclear-armed missile force would imply that North Korea might use nuclear weapons relatively early in a crisis, against ports and airfields to prevent the U.S. from amassing forces as it did against Saddam Hussein in 1991 and 2003. North Korea might see this as a war-winning strategy or hope that significant casualties would force the United States to cease hostilities.