Was there such things as a safe place if Mark's hunch was right?

According to Mark, no place will be absolutely safe. He does, however, believe that Omaha, the location of the SAC Headquarters will be the number one target. To Mark, this means that his children will have a better chance to survive in Fort Repose with Randy than with him.

"There isn't any place that'll be absolutely safe. With fallout and radiation, it'll be luck-the size of configuration of the weapons, altitude of the fireball, direction of the wind. But I do know Helen and the children won't have much chance in Omaha. SAC Headquarters has got to be the enemy's number one target. I'll bet they've programmed three five-megaton IC's for Offutt, and since our house is eight miles from the base any kind of near-miss does it "- Mark snapped his fingers-"like that. Not that I think it'll do the enemy any good-command automatically shifts to other combat control centers and anyway all our crews know their targets. But they'll hit SAC Headquarters, hoping for temporary paralysis. A little delay is all they'd need. I'll have to be there, at Offutt, in the Hole, but the least a man can do is give his children a chance to grow up, and I think they'd have a better chance in Fort Repose than Omaha.