Why Ballistic Missiles Are So Hard to Stop: Lessons from the Iran-Israel Conflict

Introduction

Explore the challenges of intercepting ballistic missiles and learn key insights from the Iran-Israel Conflict. In late 2024 and again in 2025, Iran launched huge barrages of ballistic missiles at Israel. The strikes caught global attention. Israel’s multi-layered defences from the short-range Iron Dome to the long-range Arrow system shot down most of the missiles. But shockingly, images of buildings and bases hit in central Israel showed that even a few missiles slipped through. This raises the question: why are ballistic missiles so hard to stop? The answer lies in their design, speed, and sheer numbers. Recent events show that even top defenses can be overwhelmed by enough incoming missiles.

Ballistic missiles are giant rockets that leap into high (even exoatmospheric) arcs and then fall back to Earth at hypersonic speeds. They are not guided in flight like cruise missiles; after their engines cut off, they coast on a fixed trajectory much like throwing a stone upward. This means a single missile can travel hundreds or thousands of kilometers (for example, Iran’s Fateh-110 flies – 300 km, its medium-range Qiam-1 – 700 km, and some newer Iranian missiles reach – 1,400 km). While cruising through space and the upper atmosphere at speeds of Mach 5 or higher, they are extremely hard to detect and hit. In practical terms, a missile can cover the -1,500 km from Iran to central Israel in about 15 minutes giving defenders very little time to react.

 What Are Ballistic Missiles?

A ballistic missile is essentially a rocket that rises into the sky and then follows a high, arching path (a “ballistic trajectory”) down to its target. In the boost phase, it is powered by rocket engines. After that, it coasts without power along a curve through or above the atmosphere, eventually re-entering at very high speed. The flight has three parts: 1) the powered launch (boost), 2) the mid-course (in space, unpowered), and 3) the terminal dive back through the atmosphere. Modern ballistic missiles can carry conventional or nuclear warheads; most long-range ones were built for nuclear deterrence.

Even the first big ballistic missiles were formidable. World War II’s German V-2 rocket was the first long-range weapon of this kind. Since then, the US and USSR built ICBMs that travel over 5,000 km. Today Iran and other countries have smaller versions (short- and medium-range), but they operate on the same principles. For example, Iran’s newer medium-range missiles (Shahab series, Khorramshahr, etc.) can travel around 1,000–2,000 km.

Because of the high arcs, ballistic missiles spend most of their flight outside the dense atmosphere. They re-enter at hypersonic speeds (above Mach 5), often around 20,000 km/h (13,000 mph) for longer-range missiles. A key point: after the boost, they loose propulsion. They act like unguided bullets. This flight path makes them very hard to track and intercept once they are descending. Only a few defence systems have the speed and altitude reach to even try.

Ballistic missiles are different from cruise missiles (which fly low and are powered throughout).

Why Are They Hard to Defend Against?

Ballistic missiles present a tough challenge for air defense for several reasons:

• Extreme Speed: On re-entry, many ballistic missiles exceed Mach 5 (five times the speed of sound). At these speeds, they cover ground in seconds and are difficult for radar and interceptor missiles to track and engage. Most standard surface-to-air missiles (like Patriot or S-300 series) are not designed to chase down a warhead coming in that fast. Only specialised interceptors (like Israel’s Arrow-2/3 or the US THAAD or S-400) can reach such speeds and altitudes.
• High Altitude: Ballistic missiles travel outside the atmosphere for much of their flight. Once in space, traditional air defences have no reach. The defensive “window” is only once the missile re-enters. Even then, it may re-enter over the target area at very high altitude, giving scant reaction time.
• Limited Warning Time: A missile launched from Iran might be detected by satellites or radar in a minute or two, but by the time defenders are sure of its trajectory and threat, only 5–10 minutes might remain before impact. For example, Iran’s Oct 2024 barrage was detected soon after launch, but most missiles reached Israel in about 15 minutes, barely enough time to scramble interceptors.
• Saturation Attacks: Launching many missiles at once strains defences. Each defence battery can only fire a limited number of interceptors quickly. If dozens or hundreds of missiles arrive together, even a high success rate means some will get through. As one report noted, “the larger the number of missiles, the more chance there is of at least one sneaking through”. In the recent barrage, Israel intercepted roughly 90% of inbound missiles, but with 180 fired, that still meant a few dozen missiles hit their targets.
• Countermeasures and Ballistic Nature: Ballistic missiles can carry decoys or multiple warheads to confuse defenses (though Iran’s missiles tend to have simple warheads). They follow an unpowered glide path, which is very hard to alter at the last second to dodge an interceptor. In effect, once launched, they are on a one-way trajectory like a rock dropped from a height. A defense missile must get in front of it at exactly the right point.
• Layering Complexity: Defending against ballistic threats requires multiple layers. Short-range rockets (like Gaza rockets) fall under systems like Iron Dome. But medium-range ballistic threats need systems like “David’s Sling,” and long-range ICBMs need systems like Arrow-3 or US Aegis/GMD. Each layer has blind spots and only covers certain ranges. Coordinating them perfectly is hard.

A quote from analysis of the 2025 attack sums it up: even “one of the world’s best air defense systems” can struggle with ballistic missiles. Those missiles “fly at hypersonic speeds above Mach-5, meaning very few surface-to-air batteries are capable of intercepting them” And as experts put it, it’s a game of odds: fire enough cheap rockets and statistically something gets through, even if each one is likely to be stopped.

 Historical Context

Ballistic missiles have been around for decades. After WWII, the US and USSR poured resources into them. The first long-range ballistic missile was the Soviet R-7 (1957), and over the Cold War thousands of ICBMs were built as nuclear deterrents. This ‘missile-versus-defence’ scenario goes back to at least the 1980s (the US “Star Wars” SDI program).

In modern times, several Middle East conflicts have featured ballistic missiles. During the 1991 Gulf War, Iraqi leader Saddam Hussein launched about 42 Scud missiles into Israel over a few weeks, aiming to split the US-led coalition by drawing Israel in. Despite massive alerts and some interceptions by Patriot missiles, these Scuds caused damage and 13 deaths. The era of chemical warhead fear also loomed then, though Saddam ultimately did not use them.

Iran’s program dates to the 1980s Iran-Iraq War, when Iran first bought Scuds from Libya and North Korea. Over time, Iran reverse engineered and built its own (Shahab series) and then newer solid-fuel missiles (Qiam, Sejjil) with longer range and better accuracy. By the 2010s Iran could threaten Israel with 1,000+ km missiles and has even developed hypersonic glide vehicles like the Fattah series.

Other regional actors use them too. Syrian forces and Hezbollah (in Lebanon) have Scud derivatives. In Yemen, Houthi rebels fire ballistic rockets (e.g. Burkan, Qaher) at Saudi Arabia. But no regional player has fielded ICBMs like the superpowers. Still, even these shorter missiles packed a punch. For example, in the 2006 Lebanon War, Hezbollah fired many rockets (though mostly unguided) at Israel. More recently, Iran’s current attack is said to be “the largest ballistic missile attack in history” with hundreds of missiles launched.

Ballistic missiles have evolved (longer range, accuracy, even manoeuvrable re-entry), but the basic challenge remains: the offence is relatively cheap compared to the elaborate defences needed. This has been true since Reagan’s SDI days and today. Even a well-funded defence can be overwhelmed if an attacker throws enough missiles (or decoys) at it cheaply. As one analysis put it, past missile defence studies found that “the cost dynamics favored the attacker, who had a major advantage by being able to ‘overwhelm’ the interceptors with relatively cheap warheads or decoys.”

 Iran’s Recent Missile Attacks on Israel

In October 2024, during a wider Middle East conflict, Iran directly struck Israel with a massive missile barrage. Israeli officials reported that about 180 ballistic missiles were fired from Iran toward Israel on October 1, 2024. The missiles ranged in type and range (reports mention Iranian Fateh-110, Zolfaghar, Fattah-1, and new hypersonic models). Most were medium-range (around 1,400 km) and reached Israel within 10–15 minutes of launch.

Israel’s military said it intercepted most of them. They used Arrow-3 and Arrow-2 interceptors, Patriot batteries, and U.S. naval SM-3 missiles. Iran claims to have hit some targets, but Israel reported minimal damage. Media accounts suggest about 30 of the missiles landed in Israel (around 20 at the Nevatim Airbase and others nearby). Miraculously, only a few dozen people were lightly injured or killed, largely because of strong buildings and timely shelter orders.

This strike was billed as “the largest ballistic missile attack in history,” outdoing any prior salvo.

And now, in June 2025 it’s a similar story : again hundreds of missiles and drones are being launched at Israel everyday. Israeli and U.S. defences reportedly shot down about 90% of them, but a few dozen “penetrated Israel’s complex web of air-defences”. Images showed a multi-story apartment hit in Bat Yam near Tel Aviv, and ruins of a civilian building in Gedera. These were wake-up calls: even Israel’s famous Iron Dome and Arrow layers cannot guarantee zero hits when faced with large barrages.

In 2024, Iran’s own costs for these strikes were high. Experts estimate each medium-range Iranian missile costs on the order of $12 million. Firing 180 of them (plus accompanying drones) cost Iran roughly $2.3 billion in October 2024. By contrast, Israel’s defenders at that time maybe spent a few hundred million intercepting (each Arrow interceptor cost $2–3.5 million, Patriots about $3.7M, and Iron Dome’s Tamir missiles $50k each). Because Iran launched and Israel shot down so many missiles, analysts note that defence was cheaper for Israel (relative to its GDP) than offence was for Iran. In short, Iran’s prestige strike came at a heavy bill a lesson in the cost-curve of offence vs. defence.

 Israel’s Air Defence and Their Limits

Israel has built one of the world’s most layered missile-defense shields, honed over decades of threats. Broadly, it has:

• Iron Dome: A short-range system (0–70 km range) designed to shoot down rockets and artillery shells. It uses the radar-guided Tamir interceptor (each about $50,000) and is very agile. Iron Dome’s control system is smart: it only shoots down rockets headed toward populated areas. In wars with Gaza in 2021 and 2023, it intercepted ~90% of incoming rockets. It can handle small missiles to some extent, but it was not built for heavy ballistic attacks.
• David’s Sling (Magic Wand): A medium-range defense co-developed with the U.S. It uses the Stunner missile (around $1 million each). It’s meant for threats like medium-range rockets and short ballistic missiles (range 70–300 km). It may intercept some of Iran’s lower-tier missiles or cruise missiles, but Israel has few batteries of it.
• Arrow-2/Arrow-3: Long-range systems (Arrow-2 intercepts within atmosphere, Arrow-3 in space). These are specifically built to shoot down ballistic missiles from afar. Arrow-3 interceptors are extremely fast and hit targets outside the atmosphere. However, each Arrow-3 missile costs around $62 million. The Arrows give Israel the ability to knock down incoming MRBMs mid-flight, but there are only a few batteries. They have a high success rate on tests, but if dozens of missiles arrive, only so many missiles can be fired.
• Patriot batteries and others: Israel also buys U.S. Patriots (for ballistic and aircraft threats) and has other guns and radars. During the Iran attacks, Israel used Patriot PAC-3; each Patriot missile costs about $3.7 million. The U.S. Aegis fleet in the Mediterranean also fired some SM-3s (around $28M each) to help intercept Iran’s missiles.

Despite this arsenal, the recent barrages exposed limits. Israel’s defence officials admit they “do not disclose the number of missiles fired,” but estimates suggest two or more interceptors per incoming missile. Even with 90+% success, some got through. Analysts note that Iron Dome is great against hundreds of cheap rockets from Gaza – it’s fast-firing and cheap per shot. But ballistic missiles come much faster, and defence has “only a few minutes to reach the intercept point” once they re-enter. Large barrages can swamp any defences. As one expert said of the June 2025 attack, “with barrages of hundreds of missiles at a time, even [David’s Sling] has difficulty keeping up”.

Another factor is stockpiles: firing hundreds of interceptors is expensive and can deplete Israel’s supply. In fact, analysts warned after the Oct 2024 strike and the ongoing war, that Israel faces “a looming shortage” of interceptor missiles and must ration them. For everyday readers: imagine trying to catch hundreds of bullets in the air with a few handfuls of darts you’ll catch most, but a few will slip through.

In summary, Israel’s multi-layer system is highly effective, but not perfect. Ballistic missiles exploit the residual risk. As one observer put it, scenes of missile hits “blunted” the idea of Israel’s “impenetrable” shield. Even Israel focuses its heaviest defences on vital military sites. Civilians owe much to those shelters and reinforced buildings that can withstand nearby blasts.

An Iron Dome missile defence battery on display. Iron Dome is optimised to intercept short-range rockets and drones with its radar-guided Tamir missiles. Israel’s approach shows that layered defence helps: each system covers a niche. But no single system can guarantee full protection against a large barrage of fast missiles.

Cost: Missiles vs Interceptors

One striking lesson is the cost imbalance between offence and defence. It’s usually cheaper to fire a missile than to intercept it. For example, Iran’s Fateh-110 missile costs on the order of $2–3 million each. Its Qiam-1 MRBM about $3.5 million. Some of Iran’s simple short-range rockets (like Zelzal) are around $1–1.5 million. In contrast, interceptors often cost more:

Weapon	Type	Approx. Cost (USD)
Zelzal-3 (Iranian missile)	Ballistic missile	~$1,500,000
Fateh-110 (Iranian missile)	Ballistic missile	~$2,100,000
Qiam-1 (Iranian missile)	Ballistic missile	~$3,500,000
Iron Dome Tamir interceptor	Defense missile	~$50,000
David’s Sling “Magic Wand”	Defense missile	~$1,000,000
Patriot PAC-3 interceptor	Defense missile	~$3,700,000
Arrow-3 interceptor	Defense missile	~$62,000,000

As the table shows, basic Iranian missiles cost a few million dollars each. An Iron Dome interceptor is very cheap (on the order of $50k), which is why Iron Dome can cheaply intercept small rockets. But the Arrow-3 interceptor – one of the few that can hit long-range ballistic missiles – costs tens of millions of dollars. (Even an Arrow battery’s interceptor is listed around $62M.) A single Patriot missile costs around $3.7M, similar to Iran’s cheaper missiles. David’s Sling is about $1M.

The result is a disparity: for Iran’s Oct 2024 attack, analysts estimated Iran spent about $12 million per missile on average. Israeli defence forces possibly spent $360 – 630 million shooting them all down only a few times more, but importantly cheaper relative to each side’s economy. Still, in absolute terms, protecting a city with defence missiles is very expensive. As one Israeli expert noted, “Defence is more expensive than offence” – a common adage in missile warfare. Every time a ballistic missile is fired, the defender may have to fire one or more costlier interceptors in response.

 Global Perspectives (US, Russia, China,India)

It’s not just Israel. The world’s major powers all face the Missile-Defense challenge, with varying approaches:

• United States: The US has the most layered setup. It uses Patriot and THAAD batteries (like Israel’s David’s Sling) for regional threats, Aegis warships with SM-3 missiles for midcourse intercepts, and GMD ground-based interceptors for long-range ICBMs. In recent years, the US spent over $200 billion on ballistic missile defence (BMD) deployments. Despite this, experts warn the US shield is far from perfect. For example, the Alaska GMD system (designed against ICBMs) has only a 50-60% hit rate in ideal tests. Extended-range threats (like massive Chinese missile raids) would likely overwhelm it. The US also noted that a truly wide-area defence (like shooting missiles during launch phase) would require futuristic solutions (e.g. space-based interceptors), at unimaginable cost.
• Russia: Russia fields advanced surface-to-air systems (S-300, S-400, and now S-500) designed to shoot down aircraft and some ballistic missiles. They also have the A-135 anti-ballistic system protecting Moscow (an older Soviet project). Russia stations S-400 batteries around key regions (Kaliningrad, Crimea, even near the Arctic). The Russian S-500 system, still in limited deployment, is touted as capable of higher-altitude interceptions. Russia is also developing naval and air-launched interceptors. But like all defences, theirs have limits. The same point applies: a mass missile volley could penetrate if not fully intercepted. Moreover, both Russia and China treat some missile defence as dual-use (anti-satellite capable), reflecting that pure missile defence can be philosophically controversial in deterrence terms.
• China: China has been catching up. It built its own long-range SAMs (like the HQ-9, similar to the Russian S-300) and is testing higher systems (HQ-19/26 similar to THAAD). China also keeps S-300/S-400 batteries around Beijing and its bases, and is building early-warning satellites and radars. However, even China admits its BMD is limited. It has only a few early-warning satellites and no nationwide interceptor network yet. Like Russia, China focuses on protecting leadership and strategic assets. Their doctrine treats large-scale defence against US missiles as a long-term goal, not an immediate reality.
• India: India combines home‑built and imported systems into a dense shield. It fields:
  
  • • Prithvi Air Defence (PAD) and Advanced Air Defence (AAD): Two‑tier exo‑ and endo‑atmospheric interceptors that can hit warheads in space and high in the atmosphere.
  
  
  • • Akash, QRSAM and MR‑SAM (Barak‑8): Layers for medium‑ and short‑range threats, with ranges up to 70 km (Akash), 25 km (QRSAM), and 70-100 km (MR‑SAM).
  
  
  • • S‑400 “Triumf”: Long‑range Russian system that India calls Sudarshan Chakra, capable of intercepting cruise missiles, aircraft and some ballistic missiles out to 400–600 km.
  
  
  • • AI‑driven command network: Systems like Akashteer tie radars, satellites and launchers into one quick‑reaction cloud.
  
  In May 2025’s Operation Sindoor, India shot down all incoming drones and short‑range missiles from Pakistan, showing its layered mix of guns, missiles and smart networks can stop even large raids.

In summary, no country has a foolproof “iron dome” for ballistic threats. All major powers invest billions, but analysts often conclude that missile defence favours the attacker once large numbers or clever countermeasures are in play. The Iran-Israel episodes reinforce this lesson: even well-armed Israel need help to stop the onslaught.

Conclusion

The Iran-Israel missile exchanges of 2024–25 show in real time why ballistic missiles remain a potent weapon. They fly extremely fast, high, and in numbers, making defence a race against time. Even the best air defence systems are not perfect shields at most they reduce damage and casualties, but a few launches can still cause harm. The balance of cost also matters: each Iranian missile costs a few million dollars to make, but an interceptor (especially long-range ones) can cost tens of millions to fire.

The lesson is clear: countries can defend their skies very well, but not absolutely completely. Saturation attacks, high-tech missiles, and sheer physics mean some risk always remains. Experts say the offence-defence cost gap generally favours the missile attacker. That’s why Iran’s leaders knew their direct strike was costly, the regime spent orders of magnitude more (relative to its economy) than Israel did defending. In practical terms, this may deter future attacks.

Looking forward, technology will improve defenses bit by bit (e.g. better radars, more interceptors, even lasers). But ballistic missiles themselves also improve (more speed, better guidance, hypersonic glide vehicles). Countries like the US are already planning space-based layers and next-generation interceptors, but such systems are still decades away if at all.

For now, the best answer is multiple layers and constant vigilance. The US, Russia, China, India, Israel and others will continue adding radar, more interceptors, and smarter tactics. But history shows that whenever one side gets good at shooting down missiles, the other side tries something new (faster missiles, swarms, decoys). It’s an arms race in the sky. The public should understand that “missile defence” is about managing risk, not eliminating it. The Iran-Israel conflict has taught us that even cutting-edge shields have their Shortcomings.

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Sources : en.wikipedia.org , en.interaffairs.ru , en.interaffairs.ru , jinsa.org , hrw.org , armscontrol.org , thejc.com , rutrtworld.com , missiledefenseadvocacy.org , reuters.com , missiledefenseadvocacy.org , en.interaffairs.ru , nations-militaryequipmentlist.weebly.com , trtworld.com , armscontrol.org , atlanticcouncil.org ,