On Thursday, the Federation of American Scientists, a private group in Washington that strongly supports arms control, issued an analysis of the new figures on its Strategic Security blog. The annual Pentagon release did not appear to be linked to President Obama’s visit Friday to Hiroshima, Japan, which was destroyed by an American atomic bomb almost 71 years ago.

Still, the new figures and private analysis underscored the striking gap between Mr. Obama’s soaring vision of a world without nuclear arms, which he laid out during the first months of his presidency, and the tough geopolitical and bureaucratic realities of actually getting rid of those weapons.

The lack of recent progress in both arms control and warhead dismantlement also seems to coincide with the administration’s push for sweeping nuclear modernizations that include improved weapons, bombers, missiles and submarines. Those upgrades are estimated to cost up to $1 trillion over the next three decades.