Larry Niven/Fridge

Fridge Horror

 * In Larry Niven's story The Return of William Proxmire, Robert A. Heinlein was cured of tuberculosis as a midshipman and remained in the Navy. In the resulting Alternate History, "Admiral Heinlein doesn't let the Soviets build spacecraft." So... in what kind of government does a military officer have that kind of power to make political decisions and impose them on other nations?
 * Possibly Fridge Brilliance, If Goddard was taken seriously by Heinlein, the German Rocket Club may have been cut off earlier from Goddard's research and so at the end of the war not nearly as well developed, denying the Russian's the German Rocket technology they used in the Space Race, so the Russians never got Space Travel and are trying to buy it, but denied because Heinlein is the rocket equivalent of Rickover.
 * Still a problem in that case. The US Apollo program relied heavily on the same German Rocket technology the Soviets used. Especially the scientists who headed the German program like Werner Von Braun.
 * Given that Admiral Heinlein is in charge of 'the Mars expedition', he apparently is the Director of NASA (or Commander-In-Chief US Space Command, or whatever it might be called) at this point in this alternate timeline. That would explain where he gets input into US policy decisions re: space travel.
 * As to how he enforces these decisions on the Russians? Two possibilities come to mind. One, the US negotiated one hell of a harsh set of treaty terms re: space utilization somehow. Two, the US reached space first... and chose to militarize it, meaning that we are dictating terms re: who is allowed to use space and how because we have the orbital weapons platforms and they don't.
 * Given that the story mentions orbiting solar power satellites, that means the technology exists to drop megawatt-scale high-energy beams onto the planetary surface. Option two is very likely.