Kristensen, Hans M., and Robert S. Norris

Abstract
As of early 2015, the authors estimate that the US Defense Department maintains about 4,760 nuclear warheads. Of this number, they estimate that approximately 2,080 warheads are deployed while 2,680 warheads are in storage. In addition to the warheads in the Defense Department stockpile, approximately 2,340 retired but still intact warheads are in storage under the custody of the Energy Department and awaiting dismantlement, for a total US inventory of roughly 7,100 warheads. Since New START entered into force in February 2011, the United States has reported cutting a total of 158 strategic warheads and 88 launchers. It has plans to make some further reductions by 2018. Over the next decade, it also plans to spend as much as $350 billion on modernizing and maintaining its nuclear forces.
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