When Russia provided military support to separatists in Ukraine, columns of Russian tanks were instrumental in turning back Ukrainian Army offensives and seizing government strongpoints, notably the Donetsk International Airport in January 2015. For hawks like Senator John McCain pushing for the United States to provide direct military aid to Ukraine, Javelin missiles were cited as a key weapon system that might have reversed the Ukrainian Army’s fortunes on the battlefield—and one far more practical to put into action than a main battle tank or jet fighter. However, providing missiles of undeniably American origin would also have sharply escalated the conflict between the United States and Russia. Unlike the widely exported TOW missiles or various Russian weapon systems, there was no credible way for such weapons to end up in Ukrainian hands without American authorization. Thus: no Javelins for Ukraine.

The U.S.-made FGM-148 Javelin is one of the premier portable anti-tank missile systems in the world. It’s also an expensive piece of kit, with each missile typically costing more than the targets it eliminates.

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Still, the infrared guided Javelin has proven itself in combat in Iraq, Afghanistan, and Syria and has reliable shtick that should work on virtually any tank out there—it hits them on the weak top armor. It’s also exposes its crew to less danger than the typical guided missile system. Because it’s such a lightweight system, it may end up being a first responder on the ground to emergencies that could be described as “massive, unexpected tank invasions”—a scenario the U.S. military could have faced during Operation Desert Shield, when it deployed light infantry to defend Saudi Arabia, and currently fears in the Baltics.

The Javelin is so effective that who the United States sells or gives Javelins to has become a political issue on more than one occasion. Within the U.S. military, the Javelin also looks set to transition from being purely an infantry system to being mounted on vehicles.

So How Does One Throw These Anti-Tank Spears (and Why Are They Powerful?)

The Javelin doesn’t look as sleek and deadly as its name would have you think—it resembles a clunky dumbbell slightly over one meter in length. Fortunately, you don’t need good looks to blow up a tank.

(This first appeared last year.)

The Javelin’s Command Launch Unit—CLU—has a sophisticated infrared sensor with multiple viewing modes, including 4x optical zoom, a 4x green-lit thermal view, and a 12x narrow-vision zoom activated for targeting. The seeker in the missile even provides a fourth 9x thermal viewing mode. The CLU can therefore serve as a handy scanning device for the infantry. The thermal viewers on the Javelin needs to be cooled off to function well, which theoretically takes 30 seconds, but might take a bit longer if you’re in Baghdad and it’s a breezy 120 degrees at noon. The system also incorporates multiple safeguards to avert or abort accidental launch.

The CLU, when loaded with a missile, weighs in at 50 pounds (most of the weight comes from the missile), and can be fired from a crouch or even seated position. That’s a lot lighter than the wire-guided TOW or other long-range missiles that typically required a heavy tripod. Still, it’s not exactly something you’d want to run a marathon with.

Once the firer acquires a target, locks the infrared seeker on to it and pulls the trigger, the Javelin missile is ejected out of the CLU without using its rocket motor in a “soft launch” creating relatively little back blast. Missile launch back blast not only makes it easy for opposing forces to spot the launcher after firing, but can make launching while inside a confined space (a building) a deadly risk. So the Javelin’s small backblast is very handy for keeping the operator alive. Still, the launch does blow back some gas, so you don’t want to stand directly behind it.

Afterwards, the Javelin’s gunner must… actually, the gunner could play Candy Crush on their cell phone if they wanted to, because unlike most long-range anti-tank missiles, the Javelin is a fire-and-forget system and requires no further input after lunch. The Javelin crew is free to duck into cover and concealment, rather than being forced to remain fixed in place guiding the missile towards the target, as is necessary with Semi-Automatic Command Line-Of-Sight (SACLOS) systems such as the wire-guided TOW or laser-guided AT-14 Kornet.

After launch, a Javelin shoots forward horizontally for a second before its rocket motor ignites and it climbs up 150 meters into the air, known as a “curveball” shot. It’s quite a sight, as you can see in this video.

The missile’s infrared seeker, benefiting from gyroscopes and gimbels, makes adjustments using thrusters to ensure its trajectory leads it to plunge almost vertically onto the infrared signature it was locked onto.

A Javelin fired in this manner will strike the top armor of an armored vehicle, which is generally much thinner than the frontal or even side armor. The Javelin’s 127 millimeter shaped charge warhead is estimated to penetrate the equivalent of 600 to 800 millimeters of Rolled Hardened Armor (RHA), which is not particularly impressive, given that modern tanks now feature composite armor that is extra effective against such warheads. But that doesn’t really matter: it’s still more than enough to penetrate the top armor of anything out there—at least, as long as we don’t consider other defensive system.

One common defense which sometimes does reinforce top armor is explosive-reactive armor (ERA), a layer of explosive bricks covering a tank intended to prematurely detonate the shaped charges used by missiles.

However, the Javelin has a tandem charge warhead designed to defeat ERA using a ‘precursor’ charge at the front of the warhead to take out the local ERA brick, blasting open a gap through which the main warhead can hit the tank’s conventional armor.

The Javelin can also be fired in direct attack mode, useful for hitting targets that are too close for the top attack, or that benefit from top cover, like a bunker or cave entrance. The direct-fire mode could also be effective against low flying helicopters.

One of the Javelin’s few limitations is its range—2.5 kilometers. Though adequate for most combat situations, older missiles like the TOW or Kornet boast ranges of 5 kilometers or more.

Russia is also aware of the Javelin’s capabilities—and their latest tanks feature several countermeasures intended to defeat them. New Relikt and Mechanit ERA systems feature dual layers of radar-triggered ERA plates designed to defeat tandem charge warheads. The Shtora and the newer Afganit Active Protection Systems can also deploy ‘soft kill’ multi-spectral grenades and flares designed to obscure the tank from infrared seekers or divert them to other heat sources.

However, the latest infrared sensors have also improved in their ability to see through obscuring haze and distinguish flares from the original target. And “hard-kill” active defenses designed to shoot incoming missiles down would need to be able to shoot vertically above the tank to tackle a top-attack Javelin—which the new Afganit system on the T-14 tank, with launch tubes nestled at a horizontal angle under the turret, doesn’t seem capable of doing.

So would Relikt-style ERA and soft-kill infrared defenses work against the Javelin? There’s simply no way to know for sure, unless Moscow were suddenly to invite Washington to test its anti-tank missiles against its best tanks in a friendly competition. But given that relations are too frosty for the United States to participate in Russia’s annual tank biathlon, don’t count on that happening.

So Do They Actually Work?

The Javelin was designed in the 70s and 80s, when the leaders of the U.S. military had nightmares about being overrun by endless hordes of Soviet tanks—a fear worsened by the generally poor performance of the M47 Dragon missile in use at the time.

However, the Javelin finally entered service with the U.S. military in 1996 after the Cold War had ended, and first saw action in 2003 during the U.S. invasion of Iraq.

At the time, the United States was not able to deploy troops in Northern Iraq by land, so it instead air dropped Special Forces and paratroopers that fought alongside Kurdish peshmerga fighters. In the Battle of Debecka Pass, a force of a few dozen Special Forces operators and a larger peshmerga contingent engaged and destroyed an Iraqi mechanized company of over a hundred soldiers. The U.S. force had just 4 Javelin launch units. Nineteen Javelins missiles were fired, seventeen of which hit, destroying two T-55 tanks, eight MT-LB armored personnel carriers, and several trucks. Reportedly, all of the Javelins shots were made at 2,200 meters range or further—close to or exceeding the official maximum range of the weapon—and one hit was even reported at 4,200 meters.

Javelins knocked out several more tanks during the Iraq War, including Type 69 tanks and Lion of Babylon T-72s, none of them cutting edge types. As the conventional phase of the conflict ended, the Javelins main duty soon came to ‘sniping’ smaller, softer targets. The Javelin’s precise targeting scope was ideal for spotting and taking out at long ranges insurgent heavy weapons teams armed with machine guns, missiles, or recoilless rifles, as well as the occasional pickup truck. Other weapons systems available to the infantry lacked the combination of long range and precision.

The irony of using Javelins to destroy pickup trucks and machine guns is that the roughly $80,000 Javelin missiles cost considerably more than the weapon systems they are destroying. This has reportedly has led U.S. forces to at times hold back on using the weapon in Afghanistan. Though considered a ‘lighter’ weapon than the vehicle-mounted TOW missile, significantly larger numbers of TOW missiles have been expended since 2003.

However, given that the United States spends dozens or hundreds of thousands of dollars operating expensive jet fighters dropping pricy smart missiles, or deploying large numbers of ground troops just in order to take out a few insurgents at a time, the relative costs of using Javelins as a sort of heavy sniping weapon may not be that absurd. It’s less likely to cause collateral damage than calling in an artillery strike or dropping a large, laser-guided bomb. And if that strike eliminates in a timely manner an active threat endangering the lives of friendly troops, it could save lives.

One last note of caution when evaluating the Javelin: though it may be a top-tier anti-tank weapon, it has not yet been used in combat against a modern tank, which is not true of the TOW or Kornet missile.

The Future of the Javelin

The Javelin has undergone quite a few upgrades since initial deployment in 1996—let’s take a look at three of the most important ones.

Given that the Javelin has been used primarily to hit soft targets and structures, a new version of the Javelin warhead with a deadlier blast fragmentation has been introduced, designated the FGM-148F. This new warhead is supposedly just as effective against tanks, and no costlier than its predecessors.

The Army has also been funding the development of a Lightweight Command Launch Unit. The new launch system would supposedly be 70% smaller, weigh almost half as much, and feature upgrades including modernized electronics, a new laser pointer, a high-definition color camera, and IR sensors with improved range and resolution.

Finally, a new extended range Javelin has been recently tested capable of hitting targets up to 4.5 kilometers away. This is significant, as one of the chief rationales for keeping the TOW missile as the standard vehicle-mounted anti-tank weapon was its longer range of nearly 5 kilometers. A long-range Javelin would seem to be superior.

Vehicle-mounted Javelins are now in the works. Back in the 90s, the Army reportedly experimented with a Javelin-toting ‘Warhammer’ Bradley but didn’t pursue the project. Recently, however, the U.S. Army has announced it is looking to upgrade half of its standard Stryker wheeled APCs to carry Javelins. (The other half would receive 30 millimeter autocannons). Previously, only specialized M1134 Strykers equipped with TOW launchers had any anti-tank capability.

The move to equip middle-weight personal carriers with effective anti-tank missiles mirrors Russia’s own moves to install deadly Kornet anti-tank missiles on the Epoch turret used in its new families of Bumerang, Kurganets and T-15 Armata (not the T-14) armored personnel carriers.

The Javelin would represent a more flexible weapon than the older TOWs, as the launch vehicle can move immediately out of danger after firing the Javelin. If the upgrade is implemented, even the United States’ lighter armored vehicles will be bristling with anti-tank firepower and the ability to launch precision guided missile attacks.

One interesting question is what will happen to the TOW missile, which is considered a heavier asset assigned to specialized anti-tank platoons. The newer TOW-2B Aero has a top-attack kinetic warhead with a wireless guidance system so that the launch unit is no longer literally attached to the missile—and the operator doesn’t have to remain immobile, though he or she will still need to guide the missile onto the target.

Though the TOW may have lost its advantage in range, it is optically guided rather than infrared-guided and also costs less at around $59,000. Thus, the U.S. military might keep both weapon systems so that no single system of jamming or countermeasures would be effective, and to retain a less costly long-range missile for fighting the kind of insurgent targets it continues to face in Afghanistan and Iraq.

The Political Battlefield

The Javelin is one the U.S. military’s most effective, man-portable weapon systems. They’re available to frontline infantry squads in the Marines and Army, and typically a few are stowed inside vehicles in mechanized units.

The United States has sold Javelins both to many NATO countries, including France and the United Kingdom, allies in the Middle East such as Saudi Arabia and the United Arab Emirates, and to Asian-Pacific countries including Australia, Indonesia and Taiwan.

Because of the Javelin’s capabilities, the sale of Javelins is loaded with both political considerations as well as military significance.

For example, the United States has provided 120 Javelin launch units to Estonia and 260 to Lithuania. If the Baltic states were invaded by Russian armor—not truly a likely event, but one much worried about because the small NATO countries would be hard to defend—light infantry wielding Javelins would basically serve as the Baltics’ first line of defense on the ground until NATO mobilized.

When Russia provided military support to separatists in Ukraine, columns of Russian tanks were instrumental in turning back Ukrainian Army offensives and seizing government strongpoints, notably the Donetsk International Airport in January 2015. For hawks like Senator John McCain pushing for the United States to provide direct military aid to Ukraine, Javelin missiles were cited as a key weapon system that might have reversed the Ukrainian Army’s fortunes on the battlefield—and one far more practical to put into action than a main battle tank or jet fighter.

However, providing missiles of undeniably American origin would also have sharply escalated the conflict between the United States and Russia. Unlike the widely exported TOW missiles or various Russian weapon systems, there was no credible way for such weapons to end up in Ukrainian hands without American authorization. Thus: no Javelins for Ukraine.

Theoretically, the same policy applies to various Syrian rebel groups being supplied arms by the United States, including Kurdish groups opposed by Turkey. The United States acknowledges supplying them with older TOW missiles, not Javelins.

But then we have images like this.

In February of this year, Kurdish forces near El Shadadi are seen firing a Javelin missile that destroyed truck-born IED hurtling towards their lines, destroying it before it could hit friendly forces. You can see the action in this clip.

The report of Javelin armed Kurds caused quite a stir, even while the U.S. government insists that it is not arming the rebels with Javelins. This may be disingenuous, or it could be that the Javelin came from a U.S. Special Forces unit operating alongside the Kurds, and the provisioning was ad hoc rather than part of a systematic program. Another possibility is that the Javelin came out of the stocks of a Middle Eastern country sympathetic to the rebels.

The Turkish Land Forces have lost nearly a dozen Patton tanks this year to anti-tank missiles wielded both by ISIS and Kurdish fighters, whom it also opposes. So far, it doesn’t seem any have been hit by Javelin missiles, however.

In any case, the Javelin missile remains one of the United States’ most potent systems on the ground, and one that seems set to increase in capability and be deployed on a greater number of platforms Its presence, or absence, on battlefields around the world will remain both consequential and highly scrutinized.

Sébastien Roblin holds a Master’s Degree in Conflict Resolution from Georgetown University and served as a university instructor for the Peace Corps in China. He has also worked in education, editing, and refugee resettlement in France and the United States. He currently writes on security and military history for War Is Boring.