Twenty two of the Trident missile silos were converted to each hold seven Tomahawk missiles. The result is a stealthy cruise missile platform capable of firing 154 Tomahawk missiles, a unique capability that greatly increases the US Navy’s firepower.

The precise loadout of each submarine is classified but includes some mixture of Block III Tomahawk and Block IV Tomahawk missiles.  Tomahawk Block III/C has a single 1,000 lb conventional warhead and a range of 1,000 miles. Block III/D has a payload of 166 cluster bomblets and a range of 800 miles. Each missile features multiple navigation methods and can guide itself to target by Inertial Navigation System, Terrain Contour Matching, Digital Scene Matching Area Correlator and GPS.

Tomahawk Block IV/E adds the capability for each missile to conduct reconnaissance, bomb damage assessment and retargeting. The missile can send back an image of the battle area in order, loiter while new target data is drawn up, and then substitute a new target for the old one. The missile is also significantly cheaper than previous Tomahawks.

The remaining two Trident launchers were converted for use by Navy SEALs, and feature lockout chambers for exiting the submarine underwater. The Ohio-class SSGNs can each carry 66 SEAL commandos as well as embark a combination of two midget submarines or Dry Dock Shelters.

The Ohio submarines fired their first missiles in anger on March 19th, 2011 during Operation Odyssey Dawn. USS Florida fired 93 Tomahawks against Libyan military targets. In the future, the cruise missile submarines could be used as mother-ships for Unmanned Underwater Vehicles (UUVs.)

USS Ponce:

It may seem strange for an aging amphibious transport dock to be on this list, and indeed a week ago it would not have made the cut The 43-year-old USS Ponce, launched in July 1971, served for years as a transport for U.S. Marines. Now it’s an Afloat Forward Staging Base, and the first ship in the US Navy operationally armed with a laser weapon.

Wednesday, the U.S. Navy revealed that the Laser Weapon System, or LaWS is now an operational weapons system. The laser system is cleared to be fired in combat.

The laser system is designed to target unmanned aerial vehicles, slow moving helicopters, and fast patrol craft. In a video released by the Navy on YouTube, the laser detonates a RPG-7 anti-tank rocket, burned out the engine of a small boat, and shot down a small unmanned aerial vehicle. The process appears to take a fraction of a second.

The U.S. Navy claims that, per the Geneva Convention the laser will not be used to target individual humans. It’s safe to say, however, that detonating explosive devices, fuel, or causing catastrophic damage to a vehicle could have lethal consequences for the crew.

No details exist on the range of the LaWS, or how many shots it can fire in an engagement. The laser light does not appear visible to the naked eye. The system appears to be aimed by a shipboard operator using a modified video game controller.

In a world of high cost weapons systems, one of the most remarkable things about LaWS is the cost. LaWS costs only 69 cents per shot, with apparently only one shot needed to disable a small boat. The Griffin missile, which the U.S. Navy had also considered using against small boats, costs $99,000 each. RAM, the point defense system that might otherwise engage UAVs, costs well over $250,000 per missile. LaWS even compares favorably with the 20mm cannon round fired by the Phalanx Close-In Weapons System. While we don’t know how much the entire LaWS system actually costs, these per shot numbers are encouraging.

LaWS is a 30 kilowatt laser system. The U.S. Navy plans to test more powerful 100 to 150 kilowatt systems within the next two years.

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The U.S. Marine Corps prides itself on being America’s 911 force—a fire brigade that the president can call upon to fight the nation’s battles in an emergency. Though the Marines have largely been treated as a de facto second land army over the past dozen years, the service is an integral component of the Department of the Navy and is primarily a maritime force. Therefore, the Marines—as a specialized amphibious force—argue that they need unique hardware to conduct their unique missions. While the service has many different types of weapons, here is a selection of their five key systems:

Marine Rifleman:

While not a “weapon system” in the traditional sense of the word, the Marine Corps warrior ethos and superb training make the service what it is. Every single Marine, from the lowest private to the Commandant himself is trained first and foremost as an infantryman.

Even the Marines’ naval aviators undergo nine months of infantry training as part of Officer Candidate School and the Basic School before they go off to flight school. The shared experience of fighting alongside Marines on the ground gives the service a level of cohesion that the other branches lack. Ultimately, it is the Marine Corps’ people that make it arguably the most effective branch of the armed forces.

With the United States theoretically ending combat operations in Iraq and Afghanistan, the service will shrink to a total strength of 182,000 Marines by 2017. But even at that reduced manning level, it will be nearly as large as the entire active British military.

M1A1 Abrams:

While the Marine Corps prides itself on being a strategically mobile medium-weight force, there are times when it needs the brute force of heavy armor. That brute force is provided by the General Dynamics M1A1 Abrams.

While not quite as advanced as the U.S. Army’s M1A2 SEPv2, the Marines’ M1A1 Firepower Enhancement Package suits the Marine’s purposes of supporting the service’s infantry. The Abrams is armed with a 120mm cannon and is protected with an armor matrix that incorporates depleted-uranium armor. With a 1,500hp Honeywell gas-turbine engine, it can move at more than 45 miles per hour.

The Marines are not a heavy, mechanized force in the mold of the Army’s heavy brigade combat teams. The entire Marine force has only three tank battalions—and the service has just shy of 400 tanks in total, most of which are stored in pre-positioned stocks.

AH-1Z Viper:

The Bell AH-1Z Viper is the latest iteration of the Vietnam-era Cobra attack helicopter. While outwardly the AH-1Z looks like its predecessors, it is basically a completely new machine.

The AH-1Z is powered by a pair of 1,800shp General Electric T700 turboshaft engines that is coupled with a new four-bladed composite rotor system that gives the helicopter exceptional agility. It carries a suite of advanced sensors including a Lockheed Martin target sight system and can carry the Longbow radar system. Like the Army’s AH-64E Apache, it can carry sixteen Hellfire missiles, but also adds an air-to-air punch with its ability to fire AIM-9 Sidewinder missiles.

The AH-1Z also shares many common parts with the Marines’ Bell UH-1Y Venom version of the UH-1 Huey, which helps with the services logistics. However, on the downside, the Viper and Venom are unique platforms with the Defense Department, and have not been built in huge numbers like the Army’s Apache or UH-60 Blackhawk helicopters. That means the Marines have a more difficult time keeping their machines up-to-date with the latest advances—and it costs more.

Boeing AV-8B Harrier II:

The AV-8B Harrier jump-jet affords the Marines’ expeditionary units their own organic fixed-wing air support. For the Marines, who can’t always afford ready access to heavy artillery, aircraft act as mobile fire support.

While the Harrier is not the best fighter or strike aircraft—until the Lockheed Martin F-35B Joint Strike Fighter becomes operational—it is the only short-takeoff, vertical-landing aircraft that can operate from amphibious assault ships. The subsonic attack aircraft, though perhaps a compromise in many respects, is essential to the Marines’ unique concept of operations.

The Harrier will be replaced in favor of the Joint Strike Fighter over the coming years. The service hopes to retire the venerable jet by 2025, reversing an earlier plan to keep the AV-8B in service past 2030. Instead, the Marines will keep their Boeing F/A-18A/B/C/D aircraft until the F-35B replaces those jets also.

LAV:

As a highly mobile, medium-weight force, the Marines don’t want to be weighted down by heavy armored vehicles. However, some mechanized forces are necessary.

For the Marines, many of those needs are met by versions of the General Dynamics Light Armored Vehicle series (LAV). A Marine light-armored reconnaissance battalion includes many variants of the LAV, including the LAV-25 LAV-AT, LAV-L, LAV-M, LAV-Rs and LAV-C2s, which all have their individual functions, ranging from anti-tank and anti-air to command and control.

Fast and agile, the most common LAV-25 is packed with a 25mm automatic cannon and a pair of 7.62mm machine guns. It can move at speeds exceeding 63 miles an hour.

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When it comes to lethal weapons, the U.S. Army has no shortage. Some may be too expensive, some too complex and others may be desired by politicians and defense contractors, but not the troops on the field.

Nonetheless, today's U.S. Army can generate an astonishing amount of firepower and deliver it in a variety of settings from small-war counterinsurgency to big-war mechanized combat. With that in mind, here are five of the best U.S. Army weapons: