To start everything off, Yes I do believe video games such as Call of Duty that portray war and a soldiers life should be allowed to exist. Video game designers actually try to make the video game as "realistic" as possible. If you read the reviews these creaters write out to their public, then you would see how hard they try to make it as realistic.
Though there is no reset button in a soldier's life in war, there has to be one in the game. How mad would you be if you bought the game for $60, and then you get through the first couple objectives in a mission, and then you die knowing you only had one life throughout the whole game? Well there goes your one life, go pick up another copy for another $60 to get a new soldier and a new life. Lives are put into the game to give players the re-playability factor. Meaning they could play the hours on end while dying tens to hundreds of times, but we still enjoy the game!
There are things included in these games that make it very unrealistic aswell. Some of these things are called "Perks." Perks give you an extra advantage towards your enemy. Some of these are "marathon" where you can sprint for as long as you can hold that button down. You can sprint as long as you desire, that is very unrealistic. Some soldiers carry half their body weight in their bags, making it very unlikely for someone to sprint FOREVER. Another perk is "stopping power." Oh this is everyone's favorite as it makes your bullets magically more powerful. This allows for a gun to kill in two bullets instead of 3 to 5 bullets. What soldier would not want for their guns to be that powerful! Very unrealistic! The last perk which just makes me mad to think about how fake it is is a perk called "cold-blooded." Basically, your soldier somehow mutates and now has cold blood, making thermal scopes, Apache Helicopters, enemy Spy Planes, completely useless, as these can only detect 'Human' warm blood. So basically you are a reptile in a human body. Yup, very unrealistic aswell.
Though these unrealistic things are put into the game, it allows the game to become much funner. These perks allow for players to use them to create new strategies, and play more strategically to get behind their enemy.
These games are very enjoyable. Though they do diminish the reality, it creates a product of enjoyment for everyone. I once played with a friend, and his friends. They happened to be soldiers as well. They all told me how they play the game to create strategies. while they played, they talked to each other in the military lingo. Saying "tango on your left flank" which would mean "enemy to your left side."
Some other games though, such as Medal of Honor, are extremely realistic. The weapons do the damage they are supposed to do, and there is not as much unrealistic things put into the game. They also put into the game how you can destroy buildings. In Call of Duty you put a RPG missile into the side of a building, and the wall will stay intact, with only black stain on it, which disappears about a minute or two after it hits. While in Model of Honor, you put a Missile into the side of a building, and the wall crumbles and explodes, now leaving a big hole into the side of the building.
To conclude, Yes games that portray war should be allowed to exist. They provide a sense of enjoyment. Though they diminish a front-line soldiers life, they are still and will continue to be one of the world's best series of games.
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