The first Turing gate, a mere hundred nanometers across, is forced open in 1963, at the high-energy physics laboratory in Brookhaven; three years later, the first man to travel to an alternate history takes his momentous step, and an empire is born.

For fifteen years, the version of America that calls itself the Real has used its Turing gate technology to infiltrate a wide variety of alternate Americas, rebuilding those wrecked by nuclear war, fomenting revolutions and waging war to free others from communist or fascist rule, and establishing a Pan-American Alliance. Then a nation exhausted by endless strife elects Jimmy Carter on a reconstruction and reconciliation ticket, the CIA's covert operations are wound down, and the Real begins to wage peace rather than war.

But some people believe that it is the Real's manifest destiny to impose its idea of truth, justice, and the American way in every known alternate history, and they're prepared to do anything to reverse Carter's peacenik doctrine. When Adam Stone, a former CIA field officer, one of the Cowboy Angels who worked covertly in other histories, volunteers for reactivation after an old friend begins a killing spree across alternate histories, his mission uncovers a startling secret about the operation of the Turing gates and leads him into the heart of an audicious conspiracy to change the history of every America in the multiverse--including our own.

Cowboy Angels is a vivid, helter-skelter thriller in which one version of America discovers the true cost of empire building, and one man discovers that an individual really can make a difference.

The Quiet War is over. The city states of the moons of Jupiter and Saturn, founded by descendants of refugees from Earth's repressive regimes, the Outers, have fallen to the Three Powers Alliance of Greater Brazil, the European Union, and the Pacific Community. A century of enlightenment, rational utopianism and exploration of new ways of being human has fallen dark. Outers are herded into prison camps and forced to collaborate in the systematic plundering of their great archives of scientific and technical knowledge, while Earth's forces loot their cities and settlements and ships, and plan a final solution to the'Outer problem.'

But Earth's victory is fragile, and riven by vicious internal politics. While seeking out and trying to anatomise the strange gardens abandoned in place by the Outers' greatest genius, Avernus, the gene wizard Sri Hong-Owen is embroiled in the plots and counterplots of the family that employs her. The diplomat Loc Ifrahim soon discovers that profiting from victory isn't as easy as he thought. And on Earth, in Greater Brazil, the democratic traditions preserved and elaborated by the Outers have infected a population eager to escape the tyranny of the great families who rule them.

Meanwhile, in the outer reaches of the Solar System, a rag-taggle group of refugees struggle to preserve the last of the old ideals. And on Triton, fanatical members of a cabal prepare for a final battle that threatens to shatter the future of the human species.

After a conflict fought to contain the expansionist, posthuman ambitions of the Outers, the future is as uncertain as ever. Only one thing is clear.No one can escape the consequences of war — especially the victors.