ty thread due to poor research. The US is far and away the best baseball nation. Just won the WBC with 2nd string stars. All the best players in baseball (per WAR, OPS, OPS+, ERA+, and the like) are American. Mike Trout, Aaron Judge, Bryce Harper, Goldschmidt, etc. 24 of the last 34 MVPs (AL/NL) over the last 17 seasons are American. 28 of the last 34 Cy Young winners are American. 11 of the last 17 World Series MVPs are American.
The US doesn't dominate baseball like basketball, where we can just show up and win, and the reason is the world wide talent pool for baseball is much, much larger. After soccer, baseball has the deepest talent pool by far. There's a reason there's 6 minor league levels before the MLB.
"But basketball is like the second biggest sport in the world! Talent pool is huge!"
Basketball's gameplay pretty much excludes like 98% of the population. Only 14% of men in the US (which is a relatively tall country by worldwide standards) are over 6 feet. There's only one basketball position that calls for a player under 6'4" ish, and you typically have to be an athletic freak to play it. Basketball is probably the most exclusive professional sport regarding physical build, thus the smaller talent pool of players who realistically have a shot a pro ball.