Since 2002, every Presidential administration has carried out a Nuclear Posture Review (NPR); a comprehensive policy that lays out when the United States may use nuclear weapons and what the government is currently doing with its nuclear arsenal. The first NPR was released during the Clinton administration in 1994. The NPR is considered to be a moderate document that discussed nuclear weapons in the same way in both Democratic and Republican administrations.
Carnegie NPP scholar Jon Wolfsthal explains that, currently, the U.S. is at a tipping point; during the 1990s and 2000s, the U.S. was able to walk back from the nuclear brink. Now, Wolfsthal says, Russia and North Korea are building up their nuclear arsenals, and the Trump administration appears ready to expand the role of nuclear weapons in ways the U.S. has not previously done; the Trump administration’s NPR talks about expanding role of nuclear weapons to deal with all manner of cyber and conventional attacks the U.S. government might face.
Wolfsthal elaborates on three main reasons why the U.S. holds nuclear weapons: (1) to deter enemies, (2) to reassure allies, and (3) if deterrence were to fail, to achive defense requirements. The U.S. can deter at very low levels—likely in the low hundreds—and can achieve defense needs with only a few dozen nuclear weapons. Annually, the U.S. declassifies the number of nuclear weapons in its arsenal. As of the latest declassification in 2017, the U.S. has approximately 4,000 active nuclear weapons in its stockpile, a significant decrease from its Cold War peak of 35,000 weapons. The U.S. military has stated that the U.S. currently holds more than enough nuclear weapons to fulfill its defense requirements.
A major difference between the Obama administration’s NPR and the Trump administration’s is the fact that arms control and international diplomacy, global leadership, and nonproliferation were core parts of the Obama administation’s review, Wolfsthal says. In the Trump administration’s NPR, a short section on arms control is included, though seemingly not as a primary objective.