"Even if you are not a citizen of either country, you're still a human being. You owe loyalty to your own race," Zen said.

The craggy man showed faint signs of discomfort. But when he spoke, his voice was still imperturbable. "Granting your statement, what do you propose I do?"

"Stop the Asians," Zen answered promptly. "Give us complete information on the location of their super-bomb. We'll make certain we get ours finished first and we'll use it to blow their installation out of existence." At the moment, his plan seemed feasible.

"That would create the very danger you are trying to avoid, would it not?" West pointed out. "Both super bombs would explode simultaneously. Do you think the Earth would remain in its orbit if this happened?"

"I don't know," Zen answered. "That would be up to the astronomers and the astronomical physicists to decide. In any case, if the danger is too great, we'll use ordinary weapons to touch off their super bomb. Well get the job done before they finish."

"They are working underground, in a cavern at least three thousand feet deep," West pointed out. "Do you have a weapon that will penetrate to this depth?"

"We'll build one!"

"You talk very glibly, colonel."

"Somebody has got to talk!" Zen said fiercely. "Even if they are building their bomb underground, they must have an exit for it somewhere. We'll locate their exit and drop an H-bomb on it."

"And thus destroy their bomb and the best of their scientists and engineers?"