"But their weapon will still work on us," the first said.

Tell it to the billions who'll die if this weapon works just once.

And how could any human being be sure those weapons were not working?

"How did you know the weapon would work if I moved in either direction?"

Given such costs and time, some say, the weapons should work well.

And they eventually either forgot how the old weapons worked or used them up.

They wanted to see how their new weapons worked!

And without tests, no nation seeking to develop nuclear arms could know for sure whether its weapons worked.

He knew the weapon didn't work; the stranger had said so.

If the weapon worked sufficiently quickly, there might not even be time to act against it.