Timelines And Time Patrol

The Draka are true to form in John Barnes' "Upon Their Backs To Bite 'Em." They pretend to negotiate with homo sapiens but only in order to find out how to enslave them. Knowing that the Draka will do this, the multiversal alliance called ATN (I still do not know what that means) is able to plant disinformation and hopefully to set the Draka and another interversal set of slavers against each other. Here at last is an adversary that understands the Draka and turns their own actions against them.

I knew nothing of Barnes' Timeline Wars series before reading "Upon Their Backs To Bite 'Em" but this story is an excellent introduction to that series so please let me advertise the series here:

Patton's Spaceship;
Washington's Dirigible;
Caesar's Bicycle;
Timeline Wars (omnibus).

Poul Anderson's Time Patrol battles to preserve a single timeline whereas Barnes' ATN battles between timelines. Both series share the premise that history might have gone differently at key points and that subsequent generations would have experienced very different worlds.