[PhiPsiRuss]

First Strike versus Second Strike
A first strike is not what it seems. It does not just refer to the first strike. It refers to taking out the opponents nuclear capability so that there can be no nuclear retaliation. What constitutes a first strike weapon? The traditional definition is that it must destroy a hardened silo at least 50% of the time, and be able to so in less than a half hour. Multiple warheads are budgeted for enemy silos, usually by a factor of 3 or 4 per silo.

In a classic scenario for a first strike, you attempt to take out all of the opponents nuclera assets. This scenario may also include decapitation as part of a first strike. Decapitation is where you also remove the C3 (command, control, and communications) of the enemy. After the first strike is executed, the CinC picks up the phone and asks for an unconditional surrender.

The first question would be, do we know where all of the North Korean nuclear assets are?

Nuclear Fallout and Radiation Dispersal Patterns
All nuclear weapons produce an enormous amount of radioactive material. The nastier the stuff, the shorter the half-life. Where does the fallout go? It moves with weather patterns. If Iran was nuked, Iraq would be safe. Afghanistan would not. If the U.S. was to nuke North Korea, we would have to calculate how the West Coast of the U.S. would be affected.

MAD versus FRS
Although this doesn't pertain to Iran or North Korea, it does demonstrate how nuclear policy changed during the Cold War. It also demonstrates how nuclear fallout factors into nuclear strategy. At one point, the United States and the Soviet Union both had policies of Mutually Assured Destruction (MAD.) This is the promise that the second one side gets nuked, the other side retaliates with at least a complete first strike.

MAD was believed to have been abandoned during the Nixon Administration in favor of Flexible Response Strategy (FRS.) MAD was publicly, and officially replaced with FRS by President Carter. FRS is a variation of MAD that states that limited use of tactical nuclear weapons will be used in the event of an attack of overwhelming force of conventional weapons. By the time that FRS was being considered, the Warsaw Pact held a huge numerical advantage in conventional weapons over NATO. How could detante be maintained? By deploying tactical nuclear weapons to Germany. This was a credible threat (and credibility is extremely important with deterrance.) The Warsaw Pact could not dredibly deploy tactical weapons to that theater. Why? Weather patterns. Any nuclear detonation on German soil would leave most of Western Europe unaffected, but Moscow would get nuclear fallout. For the Soviet Union to detonate multiple nuclear weapons on German soil, they would be killing millions of their own.

If anyone remembers the Pershing and Pershing II nuclear weapons, they were created for FRS.