Football is the most popular sport in America. It's popular in high school, it's popular in college, and it's the #1 grossing sport in America at the professional level with revenues of $9.5 billion for fiscal year 2012. There isn't any question that football is big business and that it is beloved by many Americans. Professional football is also the premier sport in holding its own in ratings on primetime TV week after week, and the Super bowl is the most watched event in America year after year.
There also isn't any doubt that football is the military's favorite and simpatico sport. The military teaches unity and the necessity of individuals becoming subservient to orders commanded from superior officers without hesitation. The military is not a democracy it is an autocracy. The military makes the rules and creates the orders; it is therefore your job as a solider to obey these orders, not to debate the merits of them. A good solider is a soldier that is loyal, courageous, selfless, and decisive, who works well together with a team of soldiers to carry out their specific duties or missions with precision and purpose.
A lot of the above could be used to describe what makes up a good football player on a given team, subject to the actual position that he plays. For the offense, the quarterback would be considered its general, and for the defense, most likely the middle line backer would be its general. In the NFL, there are no spontaneous plays, like you might have had on your school playground, with so-and-so just trying to wing it past his defender and some other player heading in the general direction of some signpost. Every play in the NFL is in the playbook which is itself the bible that the coaches refer to again and again and again. It is repetition, it is precise execution, and it is consistency and courage under duress that they demand from their players. The plays must be executed "as is", sure they are contingencies that players must adjust to, but that is the nature of battle.
There are plenty of military terms used in football, such as when a quarterback is "sacked", which equates to what a military does to a city that it conquers. Also, "blitz" which is probably a shorter form of blitzkrieg; when the offensive and defensive lines meet in the middle of the field that is "trench warfare" and "field general" which stands for the quarterback directing his team on the field of action.
The military and football go together. Their similarities are so striking, it's no wonder that the military isn't delighted to see that football is not only popular to play but popular to watch. Consequently, football can also be seen as a form of propaganda for the population as a whole. Propaganda that helps to indoctrinate the population that service for your team is the same as service to your country. Further, that the individual is swallowed up by the whole, that there is an elite head coach or president that will train you and direct your movements for the betterment of the team and its end result.
"Ask not what your country can do for you — ask what you can do for your country." That is one sentiment, apropos to football, but there is a better one: " …and that government of the people, by the people, for the people, shall not perish from the earth." That is democracy and true unity.