Call of Duty: Modern Warfare games necessarily glorify violence. They are about war, and - to borrow a phrase from another popular video game series - "War never changes." It's violent. It's brutal. And, of course, people die and suffer horribly. So what's the deal with Modern Warfare's White Phosphorus controversy?

Call of Duty: Modern Warfare brings back "Killstreaks," which reward you for killing set numbers of enemies without taking The Big Sleep yourself. You can earn the ability to call in airstrikes, a set of Juggernaut assault gear, mortars, turrets, gunships, and more. But one specific reward -- unlocked at level 51 -- has caused a high level of debate.

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Modern Warfare's White Phosphorus Controversy

Call of Duty Modern Warfare White Phosphorus

At level 51, players earn the ability to do what many consider to be a war crime: use White Phosphorus on enemies. This ability is unlocked after a 10-kill streak and allows you to melt the flesh of your enemies. Fun, right? Infinity Ward thinks so, based on this July tweet from the official Call of Duty account.

“Cover the battlefield with white smoke flare canisters that will disorient the enemy, and burn any that wander too close," the bottom-right photo reads.

What is White Phosphorus?

What is white phosphorus? As the name suggests, it's created from Phosphorus. When used in incendiary weapons, particles stick to the skin of the unfortunate souls on the receiving end of the assault. These particles then catch fire and continue to burn until one of two things happen: the material is exhausted or the oxygen supply is cut off. On top of that, the chemical is absorbed into one's skin -- the skin that is bubbling and burning -- and does extensive damage to the liver and kidneys. This can result in total organ failure.

To be fair, Modern Warfare uses a smoke variant, which may or may not be less dangerous. We don't know fully because, as the National Center for Biotechnology Information notes, "No studies have been conducted on the absorption, distribution, metabolism or excretion of WP following inhalation of WP smoke by either humans or animals." However, inhalation may cause "respiratory, cardiovascular, gastrointestinal, hematological, hepatic, renal, dermal and ocular, immunological, neurological, reproductive, developmental, genotoxic, and carcinogenic effects." Unfortunately, not a single government wants to step up and fund a proper study, as Newsweek notes.

The United States has admitted to using white phosphorus munitions in Iraq and against civilians in Syria. Israel infamously used them against Palestinian civilians as they tried to take shelter in schools, hospitals, and community centers.

So, what's the big deal? It's a video game.

"War never changes." This is evident in its more than 150 years of use in military engagements. And for that amount of time, many have condemned its use. The Geneva Conventions forbid the use of White Phosphorus in civilian areas. However, military targets are fair game.

True, Call of Duty and other military-related games have often glorified some of the most terrible weapons: nukes, for instance. However, game developers typically do something to tell "both sides" of the use of such a weapon in single-player campaigns. Spec Ops: The Line did this very well in what is widely regarded as one of the most horrific scenes in video game history. You can see it below, but please only watch it if you don't have a weak stomach.

The White Phosphorus killstreak perk in Modern Warfare is available only in multiplayer, which provides no context and does not effectively convey how horrible such a weapon is. “Our game is more about two sides,” Infinity Ward's multiplayer design director Geoff Smith told VG247 in defense of the contextless inclusion of white phosphorus. “There is no good guy or bad guy. You play on either one. We’re just creating this playground to play on.”

And that's the problem with Modern Warfare's use of White Phosphorus. It's a "playground." It does nothing to educate the average person about the horrors of its use, and everything to normalize it.

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