Football requires mental toughness, physical strength, strategy, practice, grit, and importantly team work. Without most of those qualities the sport itself would struggle to function. If at every collision, missed catch, or loss a participant resigned from their position or if strategy were excluded from the process, the substance of the sport would be diminished if not eliminated.
Frequently, analogies are made between preparing or entering a game and "going into battle". A battle in its most essential terms may be defined as an encounter between opposing forces.
Approximately 1,500,000 high school students participate in football each year in the United States. Millions more participate in organized sports.
https://www.aspenprojectplay.org/youth-sports-facts/participation-rates
In comparison to China where the most popular sports include badminton and table tennis, this may represent an intangible strategic advantage. A natural and experienced team camaraderie versus indoctrinated obedience could influence an outcome during an overt conflict unless the future mechanisms of war exclude human level interaction.
Art may be equally as important in national security.