The comparatively low yield of the modernized (for all intents and purposes, new) B-61-12 nuclear weapon, combined with its precision guidance system make it tempting to take off the shelf as a deterrent and actually use it like a conventional weapon. At National Interest, Zachary Keck writes:
… the bomb has a maximum yield of 50 kilotons. However, this yield can be lowered as needed for any particular mission. In fact, the bomb’s explosive force can be reduced electronically through a dial-a-yield system.
This combination of accuracy and low-yield make the B61-12 the most usable nuclear bomb in America’s arsenal. That’s because accuracy is the most important determinate of a nuclear weapon’s lethality … the more accurate the bomb, the lower the yield that is needed to destroy any specific target. A lower-yield and more accurate bomb can therefore be used without having to fear the mass, indiscriminate killing of civilians through explosive force or radioactive fallout.
… a U.S. counterforce strike against China’s ICBM silos using high-yield weapons [would] kill anywhere between 3-4 million people. Using low-yield weapons and airbursts, this figure drops to as little as 700 fatalities!
Yippee! Again, the result:
This makes using nuclear weapons thinkable for the first time since the 1940s. The B61-12 only encourages this trend further.
Of course, its use would likely lead to escalation and the use by both sides of the higher-yield nukes with the tens of millions of fatalities that have traditionally been associated with the use of nuclear weapons since the onset of the Cold War.
For more, see this article, which I have yet to read, at Reveal News, posted on July 15: Obama pledged to reduce nuclear arsenal, then came this weapon