An ICBM, or intercontinental ballistic missile, is a long-range weapon designed to deliver nuclear warheads to targets more than 5,500 kilometers (about 3,410 miles) away. That minimum range is what separates ICBMs from shorter-range ballistic missiles. In practice, most operational ICBMs can travel 10,000 kilometers or more, meaning they can strike targets on the opposite side of the planet in roughly 30 minutes.
How an ICBM Flies
An ICBM follows a ballistic trajectory, which means it’s powered by rocket engines during launch but spends most of its flight coasting through space under the influence of gravity, much like a ball thrown in an arc. The flight has three distinct phases.
During the boost phase, the missile’s rocket engines burn for about 250 seconds (a little over four minutes), accelerating it to around 7 kilometers per second, or roughly 15,600 miles per hour. This is the phase where the missile climbs out of the atmosphere. Once the engines cut off, the missile enters the midcourse phase, traveling through space on a high arc that can reach altitudes of over 1,000 kilometers. This coasting phase lasts about 20 minutes and is where the missile releases its warheads along with decoys designed to confuse defense systems. The final phase, called reentry, is when the warheads plunge back into the atmosphere toward their targets at extreme speed.
Solid vs. Liquid Fuel
Early ICBMs used liquid fuel, which had a major drawback: the missiles had to be filled with fuel and oxidizer before launch, a process that could take hours and was extremely hazardous. That made them vulnerable to a first strike because they couldn’t launch quickly.
Solid-fueled missiles solved this problem. They store their propellant in hardened casings and don’t require the complicated plumbing of liquid engines. The U.S. Minuteman missile got its name because it could be ready to fire on a minute’s notice. Solid-fueled missiles can also be housed in thick concrete silos or mounted on mobile launchers, making them harder to destroy. Today, most Western ICBMs use solid fuel, though Russia and China still operate some liquid-fueled systems. Russia’s newest heavy ICBM, the Sarmat, is a liquid-fueled missile with a launch weight of 208 metric tons and a range of up to 18,000 kilometers.
Multiple Warheads on a Single Missile
Modern ICBMs don’t carry just one warhead. Most use a technology called MIRV, which stands for Multiple Independently Targetable Reentry Vehicles. Developed in the early 1960s, this system allows a single missile to release several nuclear warheads during the midcourse phase, each aimed at a different target. A “bus” mechanism maneuvers in space for five to ten minutes, deploying warheads and decoys along slightly different paths.
The number of warheads varies by system. Russia’s Sarmat can reportedly carry up to 10 large warheads or 16 smaller ones, along with countermeasures or hypersonic glide vehicles designed to evade missile defenses. This capability is what makes ICBMs so strategically significant: a single missile can threaten multiple cities or military installations simultaneously.
Accuracy
ICBM accuracy is measured using a concept called Circular Error Probable, or CEP. This is the radius of a circle, centered on the target, within which 50% of warheads are expected to land. Modern ICBMs have CEPs measured in the hundreds of meters or less, meaning they can reliably strike specific military targets rather than just general areas. That precision matters because it determines whether a warhead can destroy a hardened target like an enemy missile silo.
Which Countries Have ICBMs
Only a handful of nations possess operational ICBMs. The two largest arsenals belong to the United States and Russia, which together hold the vast majority of the world’s intercontinental-range missiles.
- United States: Operates the Minuteman III (range of 9,650 to 13,000 km) and the submarine-launched Trident II (7,400 to 12,000 km).
- Russia: Fields the widest variety, including the mobile Topol-M and Yars systems, the older liquid-fueled SS-18, and the submarine-launched Bulava. The new Sarmat is intended to replace aging Soviet-era heavy missiles.
- China: Operates several systems including the DF-41 (12,000 to 15,000 km range) and the DF-5 series, along with submarine-launched JL-2 and JL-3 missiles.
- France: Maintains submarine-launched M51 missiles with a range over 8,000 km.
- United Kingdom: Deploys the U.S.-made Trident II on its submarines.
- North Korea: Has tested ICBMs, though the reliability and operational status of its arsenal remain uncertain.
Israel’s Jericho-3 has a reported range of 4,800 to 6,500 km, which falls just short of the ICBM threshold depending on the estimate. India and Pakistan possess nuclear weapons and ballistic missiles but have focused primarily on shorter-range systems targeting regional adversaries.
Arms Control and ICBMs
ICBMs have been at the center of nuclear arms control for decades. The most recent major agreement, the New START treaty between the United States and Russia, was extended through February 4, 2026. It placed limits on deployed strategic nuclear warheads and their delivery systems, including ICBMs. With that treaty set to expire, the future of formal limits on intercontinental missiles is uncertain.
The U.S. Replacement Program
The American Minuteman III has been in service since the early 1970s. While ongoing maintenance and small upgrades have kept it functional, the Air Force is developing a replacement called the Sentinel (designated LGM-35A). The program is enormous in scope: it will modernize 400 missiles, 450 silos, and more than 600 facilities across nearly 40,000 square miles of U.S. territory spanning six states. The transition from Minuteman III to Sentinel is designed to avoid any gap in capability, though the program has faced cost overruns and schedule pressures.