The imperatives of the military have always been one of the main drivers of technological development.
Just as smart gadgets have invaded our homes and revolutionised our lives over the last 15 years, next-level weaponry has transformed the military.
Today, militaries and irregular forces around the world are still pushing technological boundaries.
Everything from concealed roadside bombs — cheap, primitive, and deadly — to multibillion-dollar aerial lasers have transformed conventional methods of combat and altered the world’s technological and political landscape.
Here are 19 of the most important weapons of the last 15 years.
America's largest conventional bomb is precision-guided, weighs 30,000 pounds, and can blast through underground bunkers.
Boeing's Massive Ordnance Penetrator (MOP) bomb is designed to pierce 60 feet of reinforced concrete and then detonate 200 feet underground.
After the MOP's first successful test in 2007, the US Air Force ordered an arsenal of these mega-bombs, which are now considered a 'plan B' for striking at Iran's hardened nuclear facilities should the need ever arise.
The Navy's X-47B is a strike-fighter-sized unmanned aircraft with the potential to completely change aerial warfare.
Northrop Grumman's drone is capable of aerial refuelling, 360-degree rolls, and offensive weapon deployment. It's carried out the first autonomous aerial refuelling in aviation history, and has also taken off and landed from an aircraft carrier.
It cruises at half the speed of sound, and has a wingspan of 62 feet -- as well as a range of at least 2,400 miles, which is more than twice that of the Reaper drone.
The V-22 Osprey is a multitask tilt rotor aircraft that has become a staple of the Marine Corps since its introduction into service. The Osprey can take off and land vertically like a helicopter, but it can also travel at speeds approaching that of a fixed-wing plane.
The Osprey originally suffered from several worrisome accidents, including a series of fatal crashes, before it was finally officially introduced into service in 2007. The plane's later models have now become absolutely indispensable for the Marines. It has seen use in combat and rescue operations as far afield as Iraq, Afghanistan, and Libya.
The Air Force, Navy, and Marines have used the Osprey for almost every conceivable mission. It has been used for troop transport, MEDEVAC missions, supply transport, and aerial delivery; it is also being tested for use as an aerial refuelling platform.
As it can land vertically, the Osprey is also able to take part in operations normally out of bounds for traditional aircraft, which typically need hundreds of feet of runway space.
On January 27, the Navy carried out a successful test of a steerable marine-launched Tomahawk missile. Guided by an F/A-18E/F Super Hornet, the modified missile was able to change directions in flight and hit a moving maritime target.
'This is potentially a game-changing capability for not a lot of cost,' Deputy Secretary of Defence Robert Work said at the WEST 2015 conference. 'It's a 1,000-mile anti-ship cruise missile.'
The new converted Tomahawks would have a range of almost 1,000 nautical miles, allowing the US to maintain a considerable edge over rival naval powers.
On the other side of the Pacific, one of China's most threatening new military advancements is its development of its own advanced anti-ship cruise missiles. While potentially threatening to US ships, these missiles would have just half the range of the converted Tomahawk.
One of the most advanced defence systems on the planet can hunt and blast incoming missiles right out of the sky with a 100% success rate -- from a truck, no less.
With its unmatched precision, the Terminal High-Altitude Area Defence (THAAD) system can equalise conflicts around the world. With its mobility and strategic battery-unit placement, the THAAD can close the gap between mismatched military forces and take away an enemy's aerial advantage.
Impressively, the THAAD missile does not carry a warhead, instead using pure kinetic energy to deliver a 'hit-to-kill' strike to ballistic missiles inside or outside of Earth's atmosphere. Each launcher carries up to eight missiles and can send multiple kill vehicles, depending on the severity of the threat.
Weaponised lasers will likely be a feature on the battlefield of the future. Even though only one of the weapons was ever built and the program has been discontinued, the YAL Airborne Laser Testbed was an important proof of concept.
The American weapon, which was first tested successfully in 2007, was housed inside a converted 747 aircraft. The plane had the largest laser turret ever built installed on its nose. The laser was built to intercept tactical ballistic missiles midway through their flight path and in a 2010 test, the YAL succeeded in shooting down a test target.
The military decided the YAL was impractical -- in order to intercept a missile, the aircraft would have to already be in the air, while the weapon itself was expensive to fabricate, operate, and maintain. Still, it demonstrated that enormous, high-powered lasers could destroy large and fast-moving objects, and do so in midair.
If lasers ever become a feature of aerial combat, it will be because of the precedent of the YAL.
The Navy's Laser Weapon System, or LaWS, is a ship-mounted weaponised laser that can burn through enemy targets in less than 30 seconds.
The energy used to deploy a single LaWS laser shot costs approximately $US1 compared to the traditional SM-2, a similar surface-to-air system that runs $US400,000 per missile.
Earlier this year, Boeing signed a contract with the US Navy to upgrade the current software used on the laser system.
Both China and the US have developed nonlethal 'heat rays' that cause extreme pain and can aid in crowd control. The general idea behind the weapons is to heat the water just below the surface of a person's skin to induce pain, causing the target to flee without inflicting death or incapacitation.
The Chinese heat ray can target individuals at up to 262 feet away. When connected to an extra power source, the beam can hit targets at distances of 0.6 miles.
The US version of the heat ray, known as the Active Denial System (ADS), had a range of 3,000 feet and could raise the temperature of a target's skin by 130 degrees. However, the ADS was recalled by the US military without ever having been used over questions of its ethical application.
Extreme Accuracy Tasked Ordnance (EXACTO) are bullets that can change their path during flight to correct for the movement of a target or any other factors that might have driven the projectile off-course.
The bullets feature optical tips that can detect guidance lasers focused on a target. Tiny fins then guide the bullet towards that laser. The Pentagon successfully conducted a live-fire test utilising these rounds in early 2015.
If deployed, these rounds could drastically improve the accuracy of US infantry forces. The weapons would also help reduce the risks of friendly-fire incidents or of stray bullets harming civilians.
This isn't a weapon -- but it's still a game changer.
The Golden Hour, developed by US Army scientists in 2003, helped keep US soldiers alive after suffering a major battlefield injury. The box-like thermal container preserved red blood cells at a temperature that would prevent donor blood from dying under harsh environmental conditions in Iraq and Afghanistan -- all without having to use electricity, batteries, or ice to moderate the blood's temperature.
If soldiers were injured on the battlefield, there would be life-saving donor blood immediately on hand in small and easily portable containers that require no actual energy input. This allowed medics to perform transfusions quickly and efficiently when soldiers' lives were most at risk.
The container shows that not every major battlefield development is weapons related, and it demonstrates just how far technology has come in saving soldiers' lives.
The US was in huge trouble in Iraq in 2005. The American-led mission was losing ground to a growing insurgency led by Al Qaeda elements. And the US was suffering painful losses from improvised explosive devices that would rip through even heavily armoured vehicles. Insurgents were setting bombs that detonated under American personnel carriers which weren't built to withstand the insurgents' weaponry.
The heavily armoured MRAP was designed, developed, and built in a matter of months to counter the US' biggest operational challenge in Iraq. By 2009 over 21,000 of them were in service.
Developed on an accelerated schedule, the MRAP reduced US casualties from mine and IED attacks by 80%. And it provided the US and its allies with a vehicle that could operate in a new, challenging combat environment.
Each member of Navy SEAL Team Six is issued $US65,000 four-tube night-vision goggles, according to Navy SEAL Matt Bissonnette in his book, 'No Easy Day.'
Compared to the standard two-tube goggles, which Bissonnette says are similar to binoculars, the four-tube model gives soldiers a greatly expanded field of view.
The Ground Panoramic Night Vision Goggles are made in Londonderry, New Hampshire, by L-3 Warrior Systems' Insight division, Defence One reports.
Since 2010, the Pentagon has spent at least $US12.5 million on this elite military eyewear, according to Defence One.
Developed by Juliet Marine Systems, the Ghost could become the small military craft of the future.
Propped on two blade-like pontoons, the Ghost cuts through the water while maintaining enhanced balance. The design allows the ship to reduce friction and increases its stability.
The ship has also been designed for maximum stealth. It is nonmagnetic and hard to detect via sonar, making it ideal for infiltration and surveillance of enemy waters.
The Ghost can also deploy a range of offensive weapons that are similar to what an attack helicopter would carry. The vessel can be equipped with Gatling guns, Griffin missiles, and rockets launched either from its hull or from the craft's skin.
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