The World Cup is an important global event in which the US usually plays a very peripheral role. That was certainly the case this year as the US made it out of their group but lost in the Round of 16. The World Cup inevitably draws contrasts between soccer's global even universal popularity and the American people's stubborn preference for baseball. This is, of course, a false contrast as baseball is popular in much East Asia, the Caribbean and increasingly in a few other countries besides the US. Soccer, while the world's most popular sport, has failed to catch on in many parts of South Asia and is one of several popular sports in Australia, parts of East Asia and North America.
Nonetheless, perhaps simply because the World Cup is played during the baseball season, the comparisons persist. The contrasts between the sports are apparent. Soccer is a game of almost nonstop motion requiring tremendous stamina and athleticism from its players. It is also, one one level, a game of impressive simplicity and intuitiveness. The basic rules of soccer can be explained in five minutes and are relatively easy to understand. Baseball, on the other hand, is a skills based game where players who do not appear at all athletic can succeed at the highest level, if they can either pitch or hit. The rules of baseball are complex and not particularly intuitive. The rules of the game are also sufficiently unlike those of almost any other sport that they have to be learned specifically for baseball. Soccer is much closer to hockey or basketball than baseball is to cricket, its closest living relative.
These obvious contrasts obscure the major similarity between the sports, a similarity that may explain why baseball is slow to catch on in much of the world and why soccer is similarly slow to become popular in the US. Both baseball and soccer, despite different levels of motion on the field, are deceptively interesting games. In both games, the action on the field is only the surface of what is happening in the game. This is probably true of most sports, but the difference is that in both baseball and soccer the surface itself is less consistently interesting than in, for example, basketball.
Watching a pitcher pitch to a hitter is much more compelling if you have a rich understanding of the context, both players strengths and weaknesses, the situation in the game and a myriad other factors. Without knowing that, it is 30 seconds of waiting followed by somebody throwing a ball. Similarly, on its surface, World Cup soccer looks like a lot of running around on a very big field punctuated by an occasional attempt at a goal and a much more occasional actual goal. However, knowing the strategy behind setting up the very rare goals, being able to appreciate a great player who seems to be anticipating plays before they happen and understanding, again, the context and backstories, make this much more compelling watching.
Because of their reliance on information and context that is not available to the casual observer, both baseball and soccer are sports that are best understood and appreciated by people who grew up with the sport, or, relatively rarely, who have made a great effort to learn the game as adults. This helps explain why both sports are often described in words like "religion" or "way of life." A baseball fan from the Dominican Republic, Japan or the US and a soccer fan from Brazil, Italy or Germany are both fans of a game that plays an outsized role in their culture and that is part of their lives from a very young age. This is, again, somewhat true of other sports, but not to such an extreme. Basketball, for example, is reasonably popular in many countries, but does not play a role in the culture or history in most countries comparable to that of baseball or soccer.
The result of this is that soccer and baseball fans are large but somewhat closed societies, accessible only by birth and in the rare cases through intensive study. Therefore, if soccer and baseball are like religions, they are like religions that do not proselytize. This also explains why there are few countries where both soccer and baseball are popular. Korea, Japan and Mexico are the exceptions, but baseball is a clear favorite in the former two, while soccer remains the favorite sport of Mexico. Basketball, on the other hand, is popular throughout Europe, but less popular than soccer in almost every country there. Although soccer is becoming more popular in the US, this is not because of greater fan interest generated by the World Cup, but simply because more have Americans grown up playing the game than ever before. Eventually the US will join the ranks of soccer loving countries, but this will be due to age replacement, not conversion.