Here's What You Need To Remember: While the American military is not the largest on Earth, it is by far the best-trained and best-equipped force on the planet.

The United States is the most formidable military power the world has ever seen. Arguably, since the end of the Cold War, America has enjoyed a level of dominance unparalleled in history—neither Rome nor the British Empire enjoyed such a level of superiority over rival powers. While the American military is not the largest on Earth, it is by far the best-trained and best-equipped force on the planet—putting rivals like Russia and China to shame.

But it took generations to develop America’s military into the world-beating force it is today, and it wasn’t until the end of the Civil War that the U.S. fielded armies that could challenge European militaries on the battlefield. From then onwards, it took two world wars before the U.S. military finally established itself as the most dominant force on Earth.

Here are five of all-time deadliest innovations in America’s arsenal:

The Gatling Gun

First fielded during the American Civil War—which to this day is the deadliest war in U.S. history with over 600,000 military dead—the Gatling Gun was one of the first rapid fire weapons in history. Consisting of multiple barrels rotating around a central axis, the weapon—invented by Richard Gatling—solved the problem of providing sustained fires for the first time in the gunpowder age.

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Initially, the U.S. Army, due to the service’s conservative nature, was reluctant to adopt Gatling’s invention. After Gatling had improved on his initial six-barrel design that fired 350 rounds per minute, the Army did eventually adopt the new weapon. It was first used in 1864 at the Battle of Petersburg in Virginia.

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After the end of the Civil War, the Army used a 10-barrel Gatling gun that could fire 400 rounds per minute during various conflicts with the Native American population in what are now the Western states. The Maxim machine-gun eventually replaced the Gatling gun, but the crude hand-driven weapon heralded what was to come. During the brutal trench warfare of World War I, untold thousands fell to machine gun fire.

The Atomic Bomb

The United States developed the atomic bomb during the height of the Second World War under a program called the Manhattan Project. The project kicked-off in 1939 when the Advisory Committee on Uranium told President Franklin Roosevelt that the element "would provide a possible source of bombs with a destructiveness vastly greater than anything now known."

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Work on the bomb went into overdrive after the attack on Pearl Harbor on Dec. 7,1941, when, the United States formally entered WWII against Nazi Germany and Imperial Japan. Much of the urgency was driven by the belief that the Nazis were working on their own version of the bomb.

The project eventually succeeded and yielded the two weapon designs that ultimately brought the Second World War to an end. On Aug. 6 1945, a lone B-29 bomber called Enola Gay commanded by Col. Paul Tibbets destroyed the city of Hiroshima with a single 15-kiloton nuclear weapon called Little Boy. A few days later, a 21-kiloton yield weapon called Fat Man destroyed Nagasaki on Aug. 9, 1945.

Seeing the writing on the wall, the Emperor of Japan ordered an unconditional surrender. The world would never be the same with the dawn of the atomic era.

Precision-guided Weapons

Since the 1970s, one of America’s decisive advantages in war has been its ability to hit targets precisely. During most of history, war has basically been about throwing a huge volume of fire at a target with a small chance of actually hitting anything. The introduction of precision-guided weapons changed all that.

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For example, when the 8th Air Force launched a massive air raid to knock out German ball-bearing plants in 1943, it launched around 400 B-17 bombers to hit the targets. Most of the bombs—dropped at appalling cost in men and aircraft—didn’t even come close to hitting their targets. The pattern has repeated itself over and over—and entire squadrons would be launched to hit a single target. More often than not, they wouldn’t hit a thing.

That all changed towards the end of the Vietnam War. In 1972, laser-guided bombs allowed U.S. Air Force and U.S. Navy jets to hit targets precisely. Instead of dozens of jets trying to strike a single target in vain, one jet could hit multiple targets during a sortie.

While in 1972 there were only a handful of precision-guided weapons available, in 2015 almost all weapons dropped from American warplanes are precision guided. Precision-guided weapons have given U.S. forces the edge for the past 40 years—but it’s an advantage that is starting to slip as other nations develop their own equivalent weapons.

Stealth

With the development of ever more capable Soviet surface-to-air weapons during the 1960s and 1970s, the United States Air Force had to come up with a solution to defeat the ever increasing threat. The answer was stealth technology—which would reduce an aircraft’s radar cross-section and infrared signature.

Ironically, it was a Soviet scientist by the name of Pyotr Ufimtsev who first discovered the equations to develop a low radar cross-section aircraft. Ufimtsev’s work was eventually came to the attention of Lockheed engineer Denys Overholser, who then developed the configuration for the first stealth aircraft—which he called the “Hopeless Diamond”.

The Hopeless Diamond eventually evolved into the Lockheed F-117, the world’s first operational stealth aircraft in 1981. From that initial starting point, American stealth aircraft development took-off in new directions. The B-2, F-22, F-35, and pretty much every other American stealth aircraft originates from those early efforts to defeat the Soviet air defense system.

The net result today is the nearly unstoppable juggernaut that is the U.S. Air Force.

Drones

When Abe Karem first developed the Gnat—which eventually evolved in the General Atomics MQ-1 Predator—he probably could not have imagined his invention would herald a revolution in the ways wars are fought. Instead of risking lives over the battlefield, American forces can fight remotely with these new systems. While initially considered a passing fad, the past 15 years have shown that unmanned aircraft are here to stay and war will never be the same.

The MQ-1 Predator, which was first introduced over the Balkans in 1990s, is a crude aircraft. Its follow-on, the MQ-9C Reaper, is a little more sophisticated—but it’s the start of something that will change warfare forever. Aircraft like the carrier-based Northrop Grumman X-47B are starting to show the true potential of such machines.

Indeed, aircraft without pilots might be the dominant weapon during the remaining decades of this century. As recently as yesterday, Navy Secretary Ray Mabus told an audience that the U.S. Navy will never buy another manned strike fighter again after the F-35C. And if Mabus’ vision comes to fruition, unmanned aircraft will give the U.S. unmatched capabilities well into the future.

This first appeared in late 2015 and is being reprinted due to reader interest.