Did you know that the first instances of football can be found in manuals of war of ancient China? It describes a sport that was used to train the soldiers at that time and it included kicking a leather ball through hoops. This was supposedly there to train the soldiers in the art of precision and allowed them to be better warriors. This was later evolved into a game that was played between two opposing teams. Even if we look at the modern version of our football game today, we can find many elements that relate it as a war-like scenario. Just as in a war or a battle, there are two opposing sides, a field where the sport takes place, players that participate in the battle, scores are kept, and one side ultimately emerges as a victor.
One of the things that make football look like a metaphor for war is the contest between the two opposing teams. War is a contest as well; the only difference is that football players are fighting for a title or a prize, while soldiers in a battle are fighting for their country. Even in these differences, many similarities can be found. For example, both in war as well as in football, the soldiers and the players are required to wear a certain color of uniform. The soldiers and the players have to wear protective clothing such as helmets, etc. Each side and team has a flag and an emblem that they have their loyalties to. And each side and team has an objective, which is to defeat the other side.
Just like wars and battles are fought on battlefields, the game of football also takes place on a certain standardized field. The football field is a hundred yards long and this constitutes the boundaries inside which the 'battle' takes place. The real battles in wars also take place in certain confined areas and not inside cities and towns. The players in footballs are penalized if the ball goes out of bounds and they have to try very hard to keep the ball inside the boundaries in order to progress in the game. Similarly, just as a war has its casualties, so does football has its own rules that allow the referee to monitor the actions of the players. If a player does not play by the rules, he is given a warning by the referee and he might even be thrown out of the game if he breaks more than one rule more than once.
The game play involved with football is also very much similar to how a war is waged. One of the sides or teams assumes an offensive position, while the other side or team does its best to defend itself against the attack. The players in the offensive position charge against the defensive side and try to take the ball as far as they can into the opposing team's territory. This is similar to what happens in wars, where the side that is on the offensive pushes the other side deeper into its own territory in order to claim the enemy's land and win the war. The whole act of scoring a touchdown is a metaphor for this as the team takes the ball into the 'enemy's' side of the field and throws the ball there, signifying an attack. In modern terms, it can be related to having thrown a bomb in the enemy's land.
Therefore, we see that there are many similarities between football and war. Both these represent sports for their respective audiences: the spectators in case of football and the politicians in case of war. Two sides compete for a certain prize in both these events and the prize is won by the participation of soldiers or teammates. In the end, one side emerges the victor and the other side has to face defeat. This is how football is like war in many respects and it will not be too far fetched to say that many die-hard football fans would consider a football match as not being much further than war itself.