a hostile universe. But mankind was slow to learn the greatest lesson, that they had to cooperate if they were to go further. We were already living on borrowed time. Before the War, ten of eleven exploration ships sent into the galactic center had disappeared without a trace. Somewhere, buried deep in the billions of stars that formed the galactic hub, was a race that was as tough and tricky as we were—maybe even tougher. This was common knowledge, for the eleventh ship had returned with the news of the aliens, a story of hairbreadth escape from destruction, and a pattern of their culture which was enough like ours to frighten any thinking man. The worlds near the center of humanity's sphere realized the situation at once and quickly traded their independence for a Federal Union to pool their strength against the threat that might come any day. But as the Union Space Navy began to take shape on the dockyards of Earth and a hundred other worlds, the independent worlds of the periphery began to eye the Union with suspicion. They had never believed the exploration report and didn't want to unite with the worlds of the center. They thought that the Union was a trick to deprive them of their fiercely cherished independence, and when the Union sent embassies to invite them into the common effort, they rejected them. And when we suggested that in the interests of racial safety they abandon their haphazard colonization efforts that resulted in an uncontrolled series of jumps into the dark, punctuated by minor wars and clashes when colonists from separate origins landed, more or less simultaneously, on a promising planet, they were certain we were up to no good. Although we explained and showed them copies of the exploration ship's report, they were not convinced. Demagogues among them screamed about manifest destiny, independence, interference in internal affairs, and a thousand other things that made the diplomatic climate between Center and Periphery unbearably hot. And their colonists kept moving outward. Of course the Union was not about to cooperate in this potential race suicide. We simply couldn't allow them to give that other race knowledge of our whereabouts until we were ready for them. So we informed each of the outer worlds that we would consider any further efforts at colonizing an unfriendly act, and would take steps to discourage it. That did it. We halted a few colonizing ships and sent them home under guard. We uprooted a few advance groups and returned them to