The Nov. 10, 2015 Guardian did a recap of the issues raised by the B61 replacement. An excerpt:
“… In non-proliferation terms however the only thing worse than a useless bomb is a ‘usable’ bomb. Apart from the stratospheric price, the most controversial element of the B61 upgrade is the replacement of the existing rigid tail with one that has moving fins that will make the bomb smarter and allow it to be guided more accurately to a target. Furthermore, the yield can be adjusted before launch, according to the target.
“The modifications are at the center of a row between anti-proliferation advocates and the government over whether the new improved B61-12 bomb is in fact a new weapon, and therefore a violation of President Obama’s undertaking not to make new nuclear weapons. His administration’s 2010 Nuclear Posture Review said life extension upgrades to the US arsenal would ‘not support new military missions or provide for new military capabilities.’
“The issue has a particular significance for Europe where a stockpile of 180 B61s is held in six bases in five countries. If there is no change in that deployment by the time the upgraded B61-12s enter the stockpile in 2024, many of them will be flown out to the bases in Belgium, the Netherlands, Germany, Italy and Turkey.
“The row has had a semantic tone, revolving on what the definition of ‘new’ is, but arguably the only definition that counts is whether the generals and officials responsible for dropping bombs view its role in a different light as a result of its refurbishment. Referring to the B61-12’s enhanced accuracy on a recent PBS Newshour television program, the former head of US Strategic Command, Gen. James Cartwright, made this striking remark: ‘If I can drive down the yield, drive down, therefore, the likelihood of fallout, etc, does that make it more usable in the eyes of some president or national security decision-making process?’ And the answer is it likely could be more usable.”