Weapon of Peace

""We have a saying in Belka. "If you're an ambassador of peace, don't carry a spear"."

- Vita, Magical Girl Lyrical Nanoha A's (Actually, it's not a saying, it's the punchline to a joke)

Weapons are designed to hurt. Their names, however, may not reflect this.

The goal of the 'defending' faction in most wars is to defeat the enemy and achieve peace and, as a result, a weapon may be named for its supposed purpose of achieving peace. 'Peacemaker' seems to be a popular choice.

Uusally played straight, although a satirical work might play this trope for laughs. Compare I Call It Vera.

Anime and Manga

 * The Pacifista units in One Piece. Basically, huge Artificial Human Made of Diamond with Fricking Laser Beams. ouch.

Literature

 * Detritus of Discworld has a one-man siege crossbow he calls 'the Piecemaker'. This is literal, since the arrows shatter into a cloud of burning splinters on firing.
 * The novel The Tomorrow File by Lawrence Sanders is about a future United States where the Department of Defense was renamed the Department of Peace.
 * And of course let's not forget Nineteen Eighty-Four's Ministry of Peace.
 * In Known Space, the "Wunderland Treatymaker" was a huge Death Star-like disintegrator weapon that razed a planet's surface. The Kzinti soon surrendered after it was deployed, so it lived up to its name.

Tabletop Games

 * The Realm Defense Grid from Exalted is the main protective measure Creation has against the forces of the Wyld. In the First Age, it was known as the Sword of Creation, capable of redirecting elemental Essence from the entire world to nuke entire legions five times over -- but the Scarlet Empress, who now is the only one with access, didn't want her subject nations to feel so threatened by her world-sized cataclysmic superweapon. Well, you know, it's a defensive measure; it just happens to have a bit of kill-everything-in-this-subcontinent applications.

Video Games

 * Metal Gear Solid Peace Walker thoroughly deconstructs this trope.
 * In Metal Gear Solid 4: Guns of the Patriots,.
 * The biggest, baddest gun in Jak II Renegade is named 'Peacemaker'. It can be taken literally; while the other three guns require quite some skill to be effective, you just point it in the general direction of an enemy and pull the trigger. One of the strategy guides lampshades this, noting that "Piece Maker" would be a more appropriate name.
 * Lampshaded in Ratchet: Deadlocked with the Arbiter, so named because it was used to settle a legal dispute. When upgraded, it becomes the Silencer.
 * There is also a formerly high-level polearm weapon in World of Warcraft called the Peacemaker.
 * Unreal Tournament has The Redeemer, which is a Slap-On-The-Wrist Nuke.
 * In Supreme Commander, one of the Cybran weapons is named Liberator. It's a strategic missile launcher.
 * Many of the Aeon weapons have nice, peaceable seeming names, like the Mercy guided missile and the (actually purely defensive) Asylum shield vehicle.
 * Some of the Advent ships in Sins of a Solar Empire have peaceful, religious names. For example, the Illuminator Vessel "illuminates" others by hitting them with bright long-range energy beams. Then there's their powerful capital ships with names like Radiance, Rapture, Revelation, and Halcyon (a mythical bird said to calm waves).

Web Comics

 * Simultaneously used and averted with the "Serial Peacemaker," the protagonists' heavily-armed ship in Schlock Mercenary.
 * Part of the plot of Darths and Droids involved the plans for a 'Peace Moon'. AKA The Death Star.

Real Life

 * Nukes are often referred to as 'the deterrent', the idea being that their existence alone is enough to make enemy countries think twice before attacking. Of course, if two huge countries have nukes...
 * The Colt Single Action Army revolver is often referred to as the 'Peacemaker', because of its use in duels and as a self-defense weapon.
 * Peacemaker was also the name given to the Convair B-36 strategic bomber.
 * The LGM-118A Peacekeeper, also known as the MX missile (for Missile-eXperimental), was a land-based ICBM deployed by the United States starting in 1986. It was originally planned to be called "Peacemaker", but at the last minute was officially designated the LGM-118A Peacekeeper.
 * The tank was given its name because of its resemblance to a water tank and was originally designed simply to break through the stalemate presented by trench warfare. Modern tanks look nothing like a water tank and a few of them have the power to take out a small village.
 * The name was a security measure. In the workshop the paperwork described them as "water carriers," supposedly for use on the Mesopotamian Front. In conversation the workers referred to them as "water tanks" or, simply, "tanks." In October 1915 the British Landships Committee decided, for security purposes, to change its own name to something less descriptive. One of the members suggested "tank," and the committee agreed. It became the Tank Supply Committee, and the name "tank" was used in official documents and common parlance from then on.