An atomic explosion mushroom over Christmas Island in the Equatorial Pacific during U.S. experiments. This bomb was exploded from a plane. (AP Photo/Oakland Tribune) (Anonymous/ASSOCIATED PRESS)

The Obama administration, no friend of nukes, said that was about triple what the program actually cost. Kessler, though commending Ploughshares’ efforts, said they needed to re-work the numbers.

In response, Ploughshares said: “Whether we are spending $500 billion or $700 billion on nuclear weapons in the next decade -- the number is still too high.”

This prompted other anti-nuke folks to criticize Ploughshares for bad tactics. Eric Sapp, executive director of American Values Network, argued in an e-mail that “backing off the number,” is like “blood in the water . . for our opposition.”

“For better or worse, $700B is out there,” he noted in an e-mail to allies, “if we start openly backing off of it we run a BIG risk of building political and press momentum around the narrative that we just made this all up and don’t have any credibility.”

Sapp, in a piece in The Huffington Post, strongly defended the number, though he, too, said even if it were off by a bit it the cost would still be too much. “The number shouldn’t distract from the debate,” he told us, “but we didn’t just make this up.”

The debate continues.