I believe that the likely answer to this question was the start of the cold war between the USA and USSR.
In that case
jroa, you "believe" incorrectly. The Cold War had already been under way for 22 years before the US landed men on the moon.
In fact, the Cold War was precipitated by WWII and the subsequent formation of the Eastern Bloc by Stalin.
In 1946, British Prime Minister Winston Churchill delivered his famous "Iron Curtain" speech, which called for an Anglo-American alliance against the Soviets, whom he accused of establishing an "iron curtain", and which endangered Western Europe.
The so-called space race wasn't even on the agenda at that time, and didn't start until 1954-55.
Bear in mind too, it was only 4 months after the launch of
Sputnik that the US launched the first of its
Explorer satellites, which remained in orbit for more than 12 years. It also verified the existence of the Van Allen radiation belt.
Sputnik orbited for a mere 92 days.
—But then you don't accept that man-made satellites exist anyway, so apparently the USSR and the US were gonna fight it out on movie sets LOL.